Category Archives: Bottom Paint

Choosing the Right Boat Paint

There are many different boat paints and qualities, generally the more you spend the better the results. There are a variety of types including topside and bottom paints. Topside paints are meant to be used above the waterline and will not hold up under water. Bottom Paints (also called antifoulants or antifouling coatings) are pesticides that are only used below the waterline when you are trying to stop growth from occurring while your boat stays in the water over long periods of time. See Related Article>: Do I need Bottom Paint?

The type of paint you choose for your boat will depend on the type of boat you have and the environment in which it will be used.

There are two main types of boat paint: antifouling and topside. Antifouling paint is designed to prevent marine growth from attaching to the hull of the boat, while topside paint is designed for the superstructure of the boat, such as the deck and cabin.

If you plan on using your boat in saltwater, it is important to choose a paint that is specifically designed for saltwater use. Saltwater is much more corrosive than fresh water, so a saltwater-specific paint will be more durable and longer lasting.

Using your boat in freshwater, will require a different paint. There are a few different types of paint you can choose from. Freshwater-specific paints are available, but they are not necessary if you do not plan on using your boat in saltwater.

Boat Paints

Duralux High Gloss Marine Enamel is affordable and easy to apply and only recommended for above the waterline or moderate use on the bottom (a day or so in the water, not extended periods). This topside paint works best in very thin coats; see the prep recommendations found on product page on “how to use” tab. Duralux marine enamels do have a color offering in a flat finish, those are limited to their camouflage paint colors. Marine Alkyd Enamels like Duralux are effective and low cost.

A step up from the marine enamels are polyurethane enamels. These products such as Blue Water Marine Mega Gloss Polyurethane, Interlux Brightside, and Pettit Easypoxy have a better flow and gloss.

The best performing and hardest application is either Awlgrip or Awlcraft 2000. These require a more technical application and require the use of proper primers, catalyst and thinners with each application.

Typically when people discuss bottom paint on a boat they are referring to Antifouling paint. Bottom paint prevents growth of organisms that attach to the hull and can affect a vessels speed, performance, and durability when boat is kept in the water for extended periods of time. If you don’t have that problem, you may not need bottom paint. Antifouling bottom paint typically has a flat, dull finish that is used below the waterline.

There are generally two types of bottom paint both of which have several variations that create a multitude of products in the market place. The two different types or categories of bottom paint include hard bottom paint and ablative bottom paint. Related Article> What is the Difference Between Hard and Ablative Bottom Paint.

Once you have selected the type of paint you need, you will need to select a color. The color of your boat should be based on personal preference, but it is important to keep in mind that darker colors will absorb more heat than lighter colors.

Your boat paint choice ultimately depends on your budget and which boat paint colors meet the needs of your boat and usage.

Can I Reactivate Hard Bottom Paint?

Hard Bottom Paint

According to Practical Sailor Magazine, March 2013 issue, this topic was discussed. It is generally regarded that after 72 hours of exposure to air that hard bottom paints will oxidize and lose antifouling properties but test are showing otherwise. Of course you should always check with the manufacturer of your paint choice below are the guidelines to reactivate hard paint:

Launching of newly painted boats may be delayed up to 60 days after painting without sacrificing antifouling performance.
Boats painted between two and 12 months prior to launch date must be scuff-sanded with 220-grit production paper or abrasive pad before launching.
Boats painted more than 12 months prior to launch date must be lightly sanded with 100-grit production paper and recoated before launching.
Boats in the water for less than 24 hours (e.g. for in-the-water water testing) should be pressure washed lightly to remove dirt, salt or other contaminants and allowed to dry. These boats should still be considered newly painted and may be launched up to 60 days after the date of painting.
Boats in the water for more than 24 hours, but less than 30 days, should be pressure washed when hauled, then lightly sanded with 220-grit production paper immediately before re-launching. If necessary, launching may be delayed up to 60 days after the bottom has been sanded. Note: Boats re-launched within 72 hours of haulout do not need to be sanded before launching.
Boats in water for more than 30 days should be pressure washed when hauled, lightly sanded with 100-grit production paper and recoated with antifouling paint, even when re-launching will take place within 72 hours.

If there isn’t enought hard bottom paint on the surface it could flake off with sanding due to the thin layer.

What is the best paint for my boat?

A lot of factors contribute to what paint is best for your boat:

Are you painting the entire boat, or just the bottom? Is the boat in fresh water or salt water? Is your boat trailered?

What is on the bottom of the boat now: bottom paint, topside paint or gelcoat? Once an antifouling bottom paint has been applied only antifouling paint can go over it (unless you remove it). Gelcoat application is recommended over fiberglass, most resins and gelcoat. It can have difficulty adhering to other surfaces.

For topside only the Duralux Marine Enamel is an economical choice. It has several colors to choose from and features easy application.

Gelcoat is usually what is “original” to most boats; a bass boat will have metal flake mixed in. We sell metal flake that can be added to gelcoat or paint but we don’t sell any with it already mixed in.

Ablative bottom paint can help with the slime, will wear away slowly over time, and it is suitable for trailered boats. Bottom paint is applied below the waterline only.

If you need assistance selecting the right boat paint for your needs feel free to call our technical support team Monday-Friday 9am-5pm EST 888-505-2313.

Do I Need Bottom Paint on My Boat?

Most of the time when bottom paint is considered on a boat it is Antifouling paint. Bottom paint blocks growth of organisms that attach to the hull and can impact a vessels speed, performance, and durability when the boat is stored in water for extended periods of time. Antifouling bottom paint usually has a flat, dull finish that is used below the waterline. If you don’t have this challenge, you may not need bottom paint.

If you don’t have a growth problem or would like a nice shine to your boat’s bottom look to our other items like gelcoat or a topside paint for moderate water exposure or an aluminum paint with no antifouling agents. Gelcoat adheres to most gelcoats or fiberglass/resins, see how to apply gelcoat. A boat bottom with antifouling will need to have it removed via sanding, sandblasting or bottom paint remover before a different type of paint will adhere.

Hard Bottom Paint vs. Ablative Bottom Paint

Hard bottom paint is bottom paint that is a hard modified epoxy. After you apply hard bottom paint it is very durable and does not wear off. Hard bottom paints typically have a higher ratio of pesticides (usually copper) in them that are exposed in the outer surface of the bottom paint coating. As time goes by, the coating oxidizes and becomes less effective in combating marine growth. Hard bottom paint is generally used on boats when the boat sits for long periods of time without moving at all, or there is little movement of water (current/ tide) around the boat. You should not use a hard paint if you boat comes out of the water such as on a trailer or a lift. After 72 hours, the hard bottom paint will oxidize on the outer surface from the air and becomes ineffective. If you are trailering your boat, or keep it on a lift you should always use ablative bottom paint.

Ablative bottom paint, also known as self- polishing bottom paint, is softer and allows the coating to wear off at a controlled rate. Much like a bar of soap, once the boat moves in the water or there is a current and or tide, the outer layer slowly wears away. The wearing away of the self-polishing bottom paint allows for new, unoxidized paint to be exposed. Therefore, if you are trailering your boat, or it comes in and out of the water for any reason, the paint will oxidize within 72 hours. However, once placed back in service, that oxidized ablative paint wears away and exposes a new fresh outer coating with active protection. Ablative bottom paint is a newer technology then hard paint. It is the preferred bottom paint of most users since it typically lasts longer and continuously exposes a new active outer coating that protects against marine growth.

How long does bottom paint last on a boat?

In general, you should apply boat bottom paint once a year, however; some bottom paints can last for two years. If your boat is kept in the water or you use it regularly, you you have it checked annually to determine if it requires a new bottom paint coating.

For more how to use details see How to apply bottom paint to bare fiberglass or How to apply bottom paint over existing bottom paint.

How much does it cost to bottom paint a boat?

The cost to paint the bottom of your boat depends on a number of factors including the size of your boat, the paint you choose and whether you use a primer or not. Other factors include whether you will paint your boat or hire someone to paint it. For example, Biocop TF by Sea Hawk, is a popular bottom paint and currently costs $275.77 a gallon and provides theoretical coverage of 315 square feet per gallon. If the bottom surface of your boat is 700 square feet you would theoretically need to purchase three gallons (Biocop is not offered in quarts) at a total cost of $827. 31 for the three gallons.

That may seem expensive for paint, however boat bottom paint uses antifouling properties in order to protect the boat’s bottom from organisms found in saltwater and other elements.

For information on calculating how much paint you need to paint your boat bottom you can refer to our Bottom Paint Calculator.

Applying Antifouling Paint to a Pontoon Boat

If you do not have any coatings at all on the bottom of the boat, we suggest to sand the pontoons with 80 grit and then apply Tuff Stuff High Build Epoxy. It is a water tight barrier coat designed for use under the waterline and with aluminum hulls. Tuff Stuff will insure that you protect the aluminum from corrosion, and also aid in the adhesion of the antifouling paint. Use 2 coats. You can apply the 2nd coat within a couple of hours of the first coat. See detailed instructions at “How to Apply Marine Epoxy Primer”.

After you apply Tuff Stuff marine epoxy primer on hull, be sure to use an aluminum safe antifouling paint. The bottom paint needs to be applied the same day as the Tuff Stuff marine epoxy primer. Antifoulants in general are designed to repel hard growth. For soft growth you should have an additional biocide that help with the algae. Colorkote is an excellent antifoul for aluminum pontoons used in salt water and/or fresh water. For a less expensive option, see Smart Solution Metal Free Antifouling paint.

WARNING: You should only use an aluminum safe antifouling like Smart Solution. Using any other type of copper based antifouling could severely damage your pontoons and will cause corrosion, pitting and eventually holes in your pontoon boat.

If you do not need antifouling paint and are in fresh water, we suggest using one of the products located in the “How to Paint an Aluminum Jon Boat“ article.

Links:

How to Video:

Eco-Clad Bottom Paint Review

After further review on the performance of Eco-Clad as a bottom paint, we are NOT offering this product to our customer base. Eco Clad is engineered to support a natural beneficial biofilm (slime) on the coated area. However, we have heard several complaints about the products’ poor performance when it comes to keeping growth off the boat. The company has done a great job of marketing Eco Clad everywhere, and claims better fuel economy and faster speeds. This might be true, but performs only for a few months at best. After that you will see substantial marine growth and even worse fuel ecomony and speed along with the added costs of a new bottom job.

Our opinion and recommendation is to stay away from Eco-Clad unless you plan on keeping your boat in fresh water. Your are much better off using a traditional high quality bottom paint.

What is the difference in Hard Bottom Paint and Ablative Bottom Paint?

Hard Bottom Paint Vs. Ablative Bottom Paint

Bottom paint is generally used to keep the growth off of the bottom of your boat. There are generally two types of bottom paint both of which have several variations that create a multitude of products in the market place. The two different types or categories of bottom paint include a hard bottom paint, and an ablative bottom paint.

Hard Bottom Paint is bottom paint that is a hard modified epoxy. After you apply a hard bottom paint it is very durable and does not wear off. Hard Bottom Paints ypically have a higher ratio of pesticides (usually copper) in them that are exposed in the outer surface of the bottom paint coating. As time goes buy, the coating oxidizes and becomes less effective in combating marine growth. Hard bottom paint is generally used on boats when the boat sits for long periods of time without moving at all, or there is little movement of water (current/ tide) around the boat. You should not use a hard paint if you boat comes out of the water such as on a trailer, or a lift. After 72 hours, the hard bottom paint will oxidize on the outer surface from the air and becomes ineffective. If you are trailering your boat, or keep it on a lift you should always use an ablative bottom paint.

Ablative bottom paint, also known as self- polishing bottom paint, is softer and allows the coating to wear off at a controlled rate. Much like a bar of soap, once the boat moves in the water or there is a current and or tide, the outer layer slowly wears away. The wearing away of the self-polishing bottom paint allows for new, un-oxidized paint to be exposed. Therefore, if you are trailering your boat, or it comes in and out of the water for any reason, the paint will oxidize within 72 hours. However, once placed back in service, that oxidized ablative paint wears away and exposes a new fresh outer coating with active protection. Ablative bottom paint is a newer technology then hard paint. It is the preferred bottom paint of most users since it typically lasts longer and continuously exposes a new active outer coating that protects against marine growth.

Bottom Paint Cross Reference Guide

See the table below for a listing of most bottom paints and how they compare by the top manufacturers.

Bottom Paint Cross Reference Guide.

Top Performing Bottom Paints

Biocop TF	Micron 66	Odyssey HD	—
Islands 77 Plus	Micron 77	Odyssey HD	—
Colorkote	Micron Extra with Biolux*	Odyssey Triton	—
Self Polishing / Ablative Bottom Paints
Sea Hawk	Interlux	Pettit	Blue Water
Biocop TF	Micron 66	Odyssey HD	—
Islands 77 Plus	Micron 77	Odyssey HD	—
—	Micron Extra with Biolux*	Ultima SR40*	—
Cukote	Micron CSC	Ultima SSA	Copper Shield 45 Ablative
Monterey	Fiberglass Bottomkote Aqua	Hydrocoat SR*	—
		Hydrocoat
		Hydrocoat Eco
AF-33	Micron CSC	Horizons	Copper Shield 25
AF-33	ACT	Ultima SR40*	Copper Shield 25
Mission Bay	Micron CF	Vivid	Shelter Island Plus
Mission Bay CSF	Fiberglass Bottomkote Aqua	—	Shelter Island Plus
—	Fiberglass Bottomkote NT	Seamate	Copper Shield 25
Hard Modified Epoxy Bottom Paints
Sea Hawk	Interlux	Pettit	Blue Water
Tropikote	Ultra-Kote	Trinidad 75	—
Tropikote	Ultra-Kote	Trindad HD	—
—	Ultra with Biolux*	Trinidad SR*	—
—	Ultra with Biolux*	Trindad Pro*	—
Sharkskin	—	Trinidad HD	—
Talon	—	Unepoxy HRT	—
Aluminum Safe Bottom Paints
Sea Hawk	Interlux	Pettit	Blue Water
Smart Solution	Pacifica Plus	Ultima Eco	—
Smart Solution	Micron CF*	Odyssey Triton	—
Mission Bay	Trilux 33	Vivid	Shelter Islands Plus
Colorkote			Shelter Islands Plus
Water Based Bottom Paints
Sea Hawk	Interlux	Pettit	Blue Water
Monterey	Fiberglass Bottomkote Aqua	Hydrocoat SR*	—
		Hydrocoat
		Hydrocoat Eco
Mission Bay CSF	—
Outdrive Bottom Paints
Sea Hawk	Interlux	Pettit	Blue Water
Smart Solution	Trilux 33 Aerosol	Alumaspray Plus Aerosol	—
Bottom Paint Primers
Sea Hawk	Interlux	Pettit	Blue Water
Bottom Paint Primer	Primocon	Tie Coat Primer 6627	BarrierShield Primer
Islands Prime
Shawkocon
1266 Non-Sanding Primer	YPA200 No-Sand Primer	Skip Sand Primer 6998	—
Barnacle Blocker Aerosol	Primocon Aerosol
High Build Epoxy Primers
Sea Hawk	Interlux	Pettit	Blue Water
Tuff Stuff	Interprotect 2000E	Pettit Protect	Bottom Protect 70, Bottom Protect
Bottom Paint Cleaners
Sea Hawk	Interlux	Pettit	Blue Water
S-80 Wax ‘N Grease Killer	202 Fiberglass Solvent Wash	Bottom Prep D-95	973 Dewaxer
S-90 De-Waxing Etch & Cleaner	202V Low VOC Fiberglass Solvent Wash	Bio-Blue 92	—
Bottom Paint Removers / Strippers
Sea Hawk	Interlux	Pettit	Blue Water
Marine Paint Stripper	Interstrip 299E		—
Speciality
Sea Hawk	Interlux	Pettit	Blue Water
N/A	VC-17M Extra*	Black Widow Racing	—
		1959 Hard Racing Copper Bronze
Biocop TF Pint Booster

These bottom paint comparisons are the best match-ups of antifoulant brands and types by manufacturers. This information is the sole opinion of www.BottomPaintStore.com. Please consult each manufacturer for more specific product information and comparisons.

*These items are currently out of stock from the manufacturer and are considered to be on phase-out. Availability is very limited.

Here are the bottom paint compatibility and cross-references charts by bottom paint manufacturer:

Can you use water-based bottom paint over a marine epoxy primer?

Epoxy paint is a latex acrylic substance that may have a small amount of epoxy in the mix and provide a tough, durable protective coating that’s effortless to maintain. Putting a water-based bottom paint (WBP) over a solvent based primer can be done with some modified application procedures. You do NOT want to make the window, or hot coat the water based paint over the solvent based primer such as Tuff Stuff high build marine epoxy primer. If you do, it will mud crack. So instead of putting on the WBP over the Solvent Primer in the same day, you need to wait for the primer to totally cure. Then you have to sand it with 80 grit sandpaper before apply WBP. This is a lot of extra work and very difficult to sand = extremely hard surface. So the best thing to do when using a high build solvent based epoxy is to coat it with a solvent based paint. That way you skip the extra time and labor with sanding.

What is the Best Bottom Paint Money Can Buy?

Best Performing Bottom Paint

The best bottom paint that money can buy may NOT be the most expensive. You should buy the bottom paint that works best in your area. That will depend on the temperature of the water, tide changes, the nutrients in the water that feed unwanted growth, and many other factors.

The best bottom paint for you will be the bottom paint that stops the growth and does not break your wallet. If you buy the best performing bottom for the harshest fouling conditions and the warmest waters you would need Sea Hawk Paints Biocop TF or another Top Performing Bottom Paint. This provides you the absolute maximum protection against hard and soft growth on the bottom of your boat. This solution is recommended for high growth areas, or if you are trying to goes as long as you possibly can between bottom jobs. If you are in cooler climates or lower fouling conditions you would NOT need to spend the extra money on Sea Hawk Biocop TF. A better choice that is less expensive and will work in these conditions is Sea Hawk AF-33 or the equivalent.

ALUMINUM BOATS: The best bottom paint for an aluminum boat or pontoons is a copper free bottom paint. You cannot put the paints mentioned above (Copper-Based) on aluminum because they contain copper and will react like a battery causing pitting (holes) on aluminum. Therefore, we recommend an Aluminum Safe Bottom Paint. A good choice for aluminum is Sea Hawk Colorkote, it is copper free triple biocide paint safe for aluminum. If the aluminum has never been painted the best practice is to prime with high build epoxy primer like Sea Hawk Tuff Stuff to insure good adhesion and protect against corrosion. If you are painting a pontoon boat for the first time – try our Pontoon Bottom Paint Kit.

The best bottom paint for the outdrives is to brush on Smart Solution. (pint size). If your outdrive has never been painted before, you can use Barnacle Blocker Primer for priming the area application of bottom paint. A great value for this is the Premium Outdrive Bottom Paint Kit. If there is already a bottom paint on your running gear, just scuff sand and paint! Another option is to try an aerosol spray bottom paint. These are easy to apply.

For outdrives a foul release agent may be the choice for you, see here.

Do You Need Bottom Paint Thinner?

Bottom Paint is formulated to apply via brush or rolller. Under these normal application methods, there is no need to thin bottom paint (reduce bottom paint).

Bottom Paint Thinner

There are reducers for bottom paint, but these are used for spray applications, extremely hot climates (90F+) or if you applying to wood. (bottom paint should always be reduced by 20% for the first coat of bottom paint on wood.)

When used for these applications, please follow the manufacturers’ guidelines. (typically thin bottom paint no more than 10% unless barewood (20%) per application)). Be sure to use the correct thinner for the bottom paint that you are using. Do not mix competitive brands.

Don’t waste your money on bottom paint reducer unless your application meets these conditions. Otherwise, you are just spending more money thinning your bottom paint and waiting for it to dry! Remember that bottom is not like house paint, thinning bottom paint means that you are actually spreading less bottom paint over the surface. Bottom paint needs to be thick enough to repel growth as the paint film wears away over time.

What Is Bottom Paint?

What is Bottom Paint?

If you don’t know what bottom paint is, you are not alone. A boater that keeps his/her boat in the water for an extended period of time, must have bottom paint on the bottom of the hull to prevent growth (fouling) from occurring.

Bottom Paint also called antifouling paint, boat bottom paint, and anti-foul paint, is a special marine paint that is formulated with pesticides to keep those marine critters from growing on the bottom of the hull. Copper is most common pesticide used in bottom paints, and will prevent hard growth. Hard growth is considered mussels, barnacles, or any other crustacean that can attach to the bottom of the boat. Hard growth mostly occurs in warmer water and salt water. However, depending on your geographical location, hard growth will occur in fresh water and nutrient rich cool waters as well.

Some boat bottom paint also combine other pesticides (biocides) with copper to prevent soft growth. Soft growth refers to algae and grass.

What are some of the top performing bottom paints and what is the difference between them?

Biocop TF Self-Polishing Bottom Paint was developed as an alternative to tin-based antifouling paints to protect against the harshest marine environments.
Islands 44 TF™ By Sea Hawk Paints is an advanced tin-free self-polishing antifoulant that will keep your hull bottom smooth and free of organic growth over multiple cruising seasons.
Sea Hawk ColorKote Triple Biocide Antifouling is the next generation hull coating built with Sea Hawk DNA. Incorporating self-polishing, triple biocide, low-leaching chemistry, vibrant colors, and multi-season performance, this is more than an antifouling paint.
Islands 77 Plus Antifouling Paint is an alternative to tin-based antifouling paints to protect against the harshest marine environments. Using the newest biocide technology.
Pettit Odyssey is a multi-season antifouling combines controlled polishing ablative technology with a high copper content to provide a paint film strong enough to handle the tough marine environment from coast to coast.
Interlux Micron Extra provides excellent, long lasting antifouling protection against all types of fouling. Micron Extra includes Biolux, to control slime.
Micron 66 is a long lasting Self Polishing Copolymer with Biolux® formulated to provide a level of antifouling protection not previously available in any paint.
Blue Water Marine Copper Shield is a multi-season antifouling protection against barnacles, algae, and hydroids in salt and fresh water on boat bottoms only.
Aquagard® Waterbased Anti-Fouling Bottom Paint is formulated especially to prevent barnacles, algae, slime and other fouling organisms on vessels immersed in salt, brackish and fresh water. Nontoxic fumes, soap and water clean‐up.

Why do you need bottom paint? If you are going to keep your boat in the water for more than a couple of days, you will need some bottom paint!

What is the difference between Hard Bottom Paint and Ablative Bottom Paint?

Do I Need a Reducer For Bottom Paint?

Reducers help the paint to dry faster or slower, depending upon the reducer you use. There is a warm weather reducer that makes it dry slower, and a cool weather reducer that make it dry faster.

Generally speaking, reducers should only be used in extreme weather conditions, or to thin the paint for a spray application.

Here is the link to reducers for bottom paint.

How to Apply Bottom Paint Over Existing Bottom Paint

Bottom Painting is not very technical, but you must have a clean surface to insure good adhesion.

Refer to the Sea Hawk Compatibility Chart to determine if your existing coating is compatible with Sea Hawk antifoulant paint choice. To insure that your bottom paint adheres to your existing coating, it is important to have a clean prepared surface and an existing coating that is in good condition.

Known Compatibility of Existing Bottom Paint:
Power wash (pressure wash) to remove any loose paint, dirt, grease, or any other surface contaminants.
Scuff sand with 80 grit sandpaper, or scuff with a 3M Scotch-Brite® 7447 pad scrubbing thoroughly. Remove all residue and let dry.
Apply minimum of two coats of antifoulant. Allow 3 to 6 hours between coats and a minimum overnight dry. See the specific Technical Data Sheet for antifoulant being used. Some antifoulants may require more than 2 coats.

Unknown Compatibility* of Existing Antifoulant:
Power wash (pressure wash) to remove any loose paint, dirt, grease, or any other surface contaminants.
Scuff sand with 80 grit sandpaper, or scuff with a 3M Scotch-Brite® 7447 pad scrubbing thoroughly. Remove all residue and let dry.
Apply 1 coat of Bottom Paint Primer, sHAWKocon or 1283 Island Primer (see respective technical data sheet)
Apply minimum of two coats of antifoulant. Allow 3 to 6 hours between coats and a minimum overnight dry. See the specific Technical Data Sheet for antifoulant being used. Some antifoulants may require more than 2 coats.

Poor Condition of Existing Antifoulant:
If previous coating is cracking, flaking or peeling then strip antifoulant with Marine Paint Stripper, or by sanding or commercial blast. Refer to Bare Fiberglass Application Guidelines for new antifoulant application.

How To Apply Bottom Paint To Bare Fiberglass

The following steps should be taken to insure good adhesion of bottom paint to a fiberglass or gelcoated hull.

Premium Blister Protection and Adhesion System ** Best Paint Option

Sand and Clean: Sand to a uniformly frosty, dull looking surface with 80-100 grit (no ﬁner) sandpaper, rewash with S-80 Wax N’ Grease Killer or S-90 De-Wax Etch & Cleaner.
Apply Primer: Seal the surface with 2-3 coats of Tuff Stuff, or other high build epoxy primer. For Tuff Stuff, apply the ﬁrst coat of primer and allow the surface to dry to become tacky. Temperature and humidity affect the dry time, but you will know when to apply your next coat of primer once the paint ﬁlm becomes “tacky”. You should be able to ﬁrmly press your thumb into the paint ﬁlm and leave a thumbprint without any primer coming off the surface. You should use this method in between coats of primer and your ﬁrst coat of antifouling paint. When applying over multiple days, it is always best to go overnight between coats of primer instead going overnight between the ﬁnal coat of primer and the ﬁrst coat of bottom paint. Additional information can be found on the Tuff Stuff Technical Data Sheets.
Apply Bottom Paint: Apply minimum of two coats of Sea Hawk bottom paint. Allow 3 to 6 hours between coats and a minimum overnight dry. See the speciﬁc Technical Data Sheet for antifoulant being used. Some antifoulants may require more than 2 coats.

Sanding System** Better Paint Option

Sand and Clean: Sand to a uniformly frosty, dull looking surface with 80-100 grit (no ﬁner) sandpaper, remove any residue.
Apply Bottom Paint: Apply minimum of two coats of bottom paint. Allow 3 to 6 hours between coats and a minimum overnight dry. See the speciﬁc Technical Data Sheet for antifoulant being used. Some antifoulants may require more than 2 coats.

Simple No Sand System ** Good Paint Option

Apply Primer: Apply one thin coating of 1266 Non-Sanding Primer. This coating is applied at a maximum of 1-2 mils WFT. Excessive buildup can cause a lack of adhesion. Minimum dry time is 20 minutes with a maximum of one hour.
Apply Antifoulant: Apply minimum of two coats of Sea Hawk antifouling paint. Apply ﬁrst coat of antifouling within 2 hours of applying primer. Apply 2nd coat of antifouling allowing 3 to 6 hours between coats and a minimum overnight dry.

Note: Do NOT use a copper based paint on metal running gear and parts. You should use a metal free bottom paint such as Sea Hawk Outdrive Paint, priming it with Tuff Stuff first.

If the boat is taken down to gelcoat, is primer needed when applying bottom paint?

Primer for bottom paint is not necessary. However, if you use Tuff Stuff marine epoxy primer on the bare fiberglass, it will provide protection against blisters and any moisture. It will also improve adhesion to the hull. Tuff Stuff marine epoxy primer will last for many years. It cannot be applied over paint, it must be applied on gel coat (bare fiberglass). It only needs to be applied once, while bottom paint should be applied every season or two depending on your conditions.

If you decide to use Tuff Stuff, here is the link. You should apply at least two coats.

See Related Article> Application of a Marine Epoxy Primer

Application of Marine Epoxy Primer to a Boat

Marine Epoxy systems on the bottom of bare fiberglass is the best way to protect your boat against blisters. It also provides added adhesion of the bottom paint to the hull. Here are the steps that you need to take for proper application of a marine epoxy primer (barrier coat system) to the bottom of a boat.

Preparation

Clean
When painting a bare fiberglass / gel coat hull for the first time, it is extremely important that all contaminants such as grease, oil, wax, salt, or other foreign material are completed removed prior to sanding or application of a Sea Hawk System. Scrub the surface with a detergent soap and stiff bristle brush.

A. Clean and de-wax fiberglass hull with S-80 Wax N’ Grease Killer solvent based dewax. Saturate cheesecloth rag and wipe thoroughly to remove any cleaner and contaminants. Be sure to remove any residue before it dries and change rags frequently to insure contaminants are completely removed.

B. Apply S-90 De-Wax Etch & Cleaner with a maroon 3M Scotch-Brite® pad scrubbing thoroughly. Do not allow cleaner to dry on the surface and remove by flushing with water.Rinse entire surface with water and check for any beading on the surface which will indicate that wax is still present. If necessary repeat step 2 again until the surface is contaminant-free. Choose your system below.

Sand and Clean
Sand to a uniformly frosty, dull looking surface with 80-100 grit (no finer) sandpaper, rewash with S-80 Wax N’ Grease Killer , S-90 De-Wax Etch & Cleaner .

Apply Marine Epoxy Primer
Seal the surface with 2-3 coats of Tuff Stuff Epoxy Primer. Apply the first coat of marine epoxy primer and allow the surface to dry to become tacky. Temperature and humidity affect the dry time, but you will know when to apply your next coat of marine epoxy primer once the paint film becomes “tacky”. You should be able to firmly press your thumb into the paint film and leave a thumbprint without any high build marine epoxy primer coming off the surface. You should use this method in between coats of marine epoxy primer and your first coat of bottom paint.

Tip: When applying marine epoxy primer over multiple days, it is always best to go overnight between coats of marine epoxy primer instead going overnight between the final coat of marine epoxy primer and the first coat of bottom paint. When over coating Tuff Stuff Epoxy Primer it is important to meet the required over coating times in order to achieve the best adhesion because temperature and humidity control dry times. It is hard to give exact times of cure. An easier rule in epoxies is when the coating is dry to the touch, yet still has some tack, it is ready to be over coated. However, if the coating is completely cured (after 24 hours) it needs to be thoroughly sanded with 80 grit sand paper to remove shine. If the marine epoxy primer is not sanded after full cure, bottom paint will not adhere.

Apply Bottom Paint to Marine Epoxy Primer
Apply minimum of two coats of bottom paint. Allow 3 to 6 hours between coats and a minimum overnight dry. See the specific Technical Data Sheet for bottom paint being used. Some bottom paint may require more than 2 coats.

Painting an Aluminum Outdrive

Outdrives are difficult to keep free of growth. The main reason for this is that traditional copper-based bottom paints cannot be used on an aluminum outdrive. Doing so will result in serious corrosion from the aluminum reacting to the copper in the paint.

Colorkote When painting an aluminum outdrive you must use a copper-free bottom paint. There are a couple of different brands out there: Interlux, Blue Water Marine, and Sea Hawk to name a few. However, you will get the best possible results with Tuff Stuff Primer and Colorkote.

The Outdrive Paint shows best results when paired with a primer such as Tuff Stuff. These products are usually applied by brush and roller.

An alternative to painting is a foul release system, such as PropGlide. For more information on Propglide, see this How To Article.

What’s The Difference Between Freshwater and Saltwater Bottom Paint?

Typically there is less growth in fresh water than in salt water. For that reason, bottom paint used in fresh water usually have less active ingredients (copper, zinc, etc.) to prevent growth. Most bottom paint for salt water can be used in fresh water. However, there are some exception, such as, Interlux Micron 66. This paint is limited to salt water only. Using Micron 66 bottom paint in fresh water, or where there is a lot of fresh water run off, will result in failure of the coating.

Consider using a bottom paint that is good in both fresh water and salt water. All of Sea Hawk Paints , Blue Water, Pettit or Interlux bottom paints are good for either types of waters and are considered both fresh water bottom paint and salt water bottom paint. You never know where you might travel that will have significant fresh water run off!

Keep in mind that you probably don’t need the top performing paint like Sea Hawk Biocop TF bottom paint if you are in fresh water. You can go with a less expensive alternative like Copper Shield 25, AF-33 or Talon. Anything more is probably over kill!

Preparing Your Boat for a Bottom Paint Job

Preparation is key when painting on any surface. Applying bottom paint is not the cleanest of jobs, but it is really simple to do. Below you will find the exact steps to insure a good bottom paint job, whether you have a new boat, or a boat that has existing bottom paint on it.

Preparation for Bare Fiberglass
When painting a bare fiberglass gel coat hull for the first time, it is extremely important that all contaminants such as grease, oil, wax, salt, or other foreign material are completed removed prior to sanding or application of a Sea Hawk System. Scrub the surface with a detergent soap and stiff bristle brush.

Clean your boat following options A or B

A. Clean and de-wax fiberglass hull withS-80 Wax N’ Grease Killer solvent based dewax. Saturate cheeseclothrag and wipe thoroughly to remove any cleaner and contaminants. Be sure to remove any residue before it dries and change rags frequently to insure contaminants are completely removed.

B. Apply S-90 De-Wax Etch & Cleaner with a maroon 3M Scotch-Brite® pad scrubbing thoroughly. Do not allow cleaner to dry on the surface and remove by flushing with water.Rinse entire surface with water and check for any beadingon the surface which will indicate that wax is still present. If necessary repeat step 2 again until the surface is contaminant-free. Choose your system below.

Sand & Clean

Sand to a uniformly frosty, dull looking surface with 80-100 grit (no finer) sandpaper, rewash with S-80 Wax N’ Grease Killer , S-90 De-Wax Etch & Cleaner .

Apply Bottom Paint
Apply a minimum of two coats of Sea Hawk bottom paint. Allow 3 to 6 hours between coats and a minimum overnight dry before launching. See the specific Technical Data Sheet for the bottom paint you are using. Some bottom paint may require more than 2 coats.

Tip: Epoxy systems on the bottom of bare fiberglass is the best way to protect your boat against blisters. It also provides added adhesion of the bottom paint to the hull.

Preparation Over Existing Bottom Paint

Clean the boat
Clean the existing boat bottom paint with a pressure washing. If you have excess build up of growth, you can remove this by scraping and/or using muratic acid. Try to get all growth residue off the existing old bottom paint so that you have good adhesion of the new bottom paint.

Scuff Sand the surface
Scuff sand to a dull looking surface with 80-100 grit (no finer) sandpaper, then rinse with water and allow to dry. If your old bottom paint is really chalky, consider giving it a more agressive sanding to insure proper adhesion of the new bottom paint.

Apply Bottom Paint
Apply minimum of two coats of Sea Hawk bottom paint. Allow 3 to 6 hours between coats and a minimum overnight dry before launching. See the specific Technical Data Sheet for bottom paint being used. Some bottom paint may require more than 2 coats.

Sea Hawk Ablative Bottom Paint Rankings by Antifouling Performance

Sea Hawk Ablative Bottom Paint Rankings by Antifouling Performance

Rank	Bottom Paint Name	Fresh Water / Salt Water	High Growth Area Performance	Slime Fighting	Warm Water Performance	Cost	Comments
1	Islands 77 Plus	Both	*****	*****	*****	$$$$$	Top Performance for Highest Growth Areas (Non-US)
1	Biocop TF	Both	*****	*****	*****	$$$$$	Top Performance for Highest Growth Areas (US)
2	Cukote Biocide Plus	Both	****	***	****	$$$$	Best Value Multi-Seasonal with Slime Fighter
3	Cukote	Both	***	n/a	***	$$$	Best Overall Value Multi-Seasonal
4	Monterey	Both	***	n/a	***	$$	Best Value Water-Based Multi-Seasonal
5	AF-33	Both	***	n/a	***	$	Lowest Cost Multi-Seasonal Available
6	Smart Solution	Salt	**	n/a	**	$$	Metal Free Best Choice for Aluminum in salt water
7	Mission Bay	Fresh	**	n/a	**	$$$	Best Choice for Aluminum and Pontoons. Safe on Aluminum.
8	Mission Bay CSF	Both	**	n/a	**	$$$	Environmentally friendly water-based and copper free. Best for apply indoors.
9	VMG Racing Finish	Fresh	*	n/a	*	$	Best used in Fresh Water Only, or as a Smooth Racing Finish

Ranking: By Most Effective Antifouling Performance
* All rankings provided by Bottom Paint Store are based on customer feedback, product testing data, and current market prices.

How to Apply Bottom Paint to an Aluminum Boat

Bottom paint is an essential part of protecting your aluminum boat from the elements. Be sure to choose a bottom paint that is specifically designed for aluminum boats. Some bottom paints can actually cause corrosion on aluminum, so it’s important to make sure you get the right type of paint. Apply the bottom paint according to the manufacturer’s instructions. In general, you’ll want to apply two coats for best results.

Here are a few tips on how to apply bottom paint to ensure optimal results.

KEY TAKEAWAYS FOR HOW TO PAINT AN ALUMINUM BOAT

Prepare the Surface
The first step in painting an aluminum boat is to prepare the surface. This includes cleaning the boat with soap and water, sanding it down, and applying a primer. The primer will help to create a smooth surface for the paint to adhere to.
Choose the Right Paint
It is important to choose the right paint for an aluminum boat. A good choice would be a marine-grade paint that is specifically designed for aluminum boats. This type of paint will be able to withstand the elements and will not peel or chip easily.
Apply the Paint
Once you have chosen the right paint, you can begin to apply it to the boat. It is best to use a brush or roller for this task. Start by painting the hull of the boat and then move on to the deck. Be sure to apply an even coat of paint and allow it to dry completely before applying a second coat.

Tuff Stuff Marine Epoxy Primer

Begin by pressure washing your boat, and scrubbing any debris, dust, contaminants and marks off the boat surface so it is totally clean. Give your boat a final rinse and dry. If you do not have any coatings at all on the bottom of the boat, we suggest to sand the hull with 80 grit and then apply Tuff Stuff High Build Epoxy. It is a water tight barrier coat designed for use under the waterline and with aluminum hulls. Use 2 coats. You can apply the 2nd coat within a couple of hours of the first coat. (up to 6 days)

After you apply Tuff Stuff marine epoxy primer on hull, be sure to use an aluminum safe bottom paint. The bottom paint needs to be applied the same day as the Tuff Stuff marine epoxy primer. Bottom paints in general are designed to repel hard growth. Colorkote is an excellent triple biocide bottom paint for aluminum hulls when in salt water. We recommend Mission Bay for fresh water. I have listed links below to the products described above. These can be brushed, sprayed, or rolled. If you already have coating(s) on the hull, pressure wash, sand with 80 grit, and then apply your paint choice.

Links:

How to Video: Aluminum Boat Bottom Paint Application

See here for all aluminum safe bottom paints.

Micron CSC by Interlux Vs. Cukote by Sea Hawk

Cukote Bottom Paint Has Clear Advantages over Micron CSC Bottom Paint!

Harder Ablative Provides Longer Lasting Performance compare to Interlux Micron CSC!
Harder Ablative Provides More Durable Coating for Trailerable Boats
Made in the USA with USA Premium Raw Materials VS. European Made and Owned
More Copper (Sea Hawk Cukote has over 47% Vs. 37% for Micron CSC)
Proven Premium Performance in All Waters!
Compatible with Micron CSC (You can apply Cukote over the top of Micron CSC without any additional steps!)
One-Year Written Guarantee Against Barnacles

Apply Directly over Micron CSC or any other Bottom Paint and Receive…

1 Year Written Guarantee Against Barnacle Growth!

Trilux 33 by Interlux Vs. Mission Bay by Sea Hawk

Mission Bay Bottom Paint Has Clear Advantages over Trilux 33!

30% Longer Lasting Performance than Interlux Trilux 33 !
US Made with Premium Raw Materials VS. European
Completely Safe for Aluminum Boats, Including Pontoon Boats!
No Copper (Trilux 33 has liquid copper)
Proven Premium Performance in All Waters!
Solvent Free Version Available (Mission Bay CSF -Easy application, Less Toxic Fumes and VOC’s)
Compatible with Trilux 33 (You can apply Sea Hawk Mission Bay over the top of Trilux 33 without any additional steps!)

This Sea Hawk Mission Bay and Interlux Trilux 33 bottom paint review / comparison was based on customer feedback and information received by the manufacturer(s) either directly or indirectly, and is solely the opinion of Bottom Paint Store.

Aquagard Vs. Monterey by Sea Hawk

Monterey Bottom Paint Rated for 24+ Months over Aquagard Bottom Paint!

Longer Lasting Performance than Aquagard! Monterey is a Multi-Season Bottom Paint!
Made in the USA with USA Premium Grade Raw Materials
Lower VOC Means More Friendly Application!
More Copper (Monterey has over TWICE AS MUCH COPPER as Aquagard (55% Vs. 26% for Aquaguard)
Proven Premium Performance in All Waters!
Compatible with Aquaguard (You can apply Monterey over the top of Aquagard without any additional steps!)
Rated by Practical Sailor for 24+ Month Bottom Paint Protection
Sea Hawk Paints Monterey Has a One-Year Written Guarantee Against Barnacles!

Apply Directly over Aquaguard or any other Bottom Paint and Receive…

1 Year Written Guarantee Against Barnacle Growth!