Interlux ACT, antifouling paint
Interlux Interlux Bottomkote ACT
  • Interlux ACT, antifouling paint
  • Interlux ACT Color Chart

Interlux ACT Ablative Antifouling Bottom Paint

Interlux ACT bottom paint provides premium seasonal antifouling protection in moderate to heavy fouling areas from algae, slime, barnacles, and zebra mussels. It is compatible with (and can be applied over) other antifouling paint as long as that coating is in acceptable condition.

'ACT' stands for Interlux's Ablative Copolymer Technology, which constantly exposes fresh biocide for anti-fouling protection throughout the season. ACT eliminates the problem of old coating buildup and associated need for heavy sanding to remove. This paint is very effective at controlling shell fouling such as barnacles and zebra mussels, keeping the bottom cleaner longer.

Not for use in California.

$60.01 / qt
 The item was added to your wishlist.
 The item was added to your shop cart.
Tech Spec Product Info User Generated Content
Note: ACT with Slime Fighter has been retired by Interlux. ACT is still available in the classic formula, but no longer contains Irgarol.



BARE FIBERGLASS - (POLYESTER OR VINYLESTER): Scrub the surface thoroughly with using a stiff brush and Interlux All Purpose Boat Soap. Rinse with fresh or salt water to remove loose dirt. Flush with fresh water to remove the soap residue and allow to dry. Remove mold release wax using one of the following methods. Apply Fiberglass Surface Prep YMA601 with a maroon, 3M Scotch-BriteTM pad and scrub well. Flush with fresh water or wipe off with a clean, wet cloth ensuring that no traces of Fiberglass Surface Prep remain. An alternative method would be to dampen a cheesecloth with Interlux Fiberglass Solvent Wash 202. Wipe thoroughly to remove all surface contamination and cleaners. Wipe off with a clean, dry rag before liquid dries. To be certain the contamination has been removed, run water over the surface. If the water beads up or separates, repeat one of the above methods. When the water sheets off, all contamination has be removed. Sanding does not remove contamination. After the surface has been properly prepared follow the application system below.

Bare Fiberglass - No Sanding System: Clean surface as above. Apply one thin, continuous coat of Interlux Fiberglass No-Sand Primer with brush or roller (do not spray; do not sand). Follow application guidelines for the primer and apply Fiberglass Bottomkote ACT.

Bare Fiberglass -Sanding System: Clean the surface following the preparation procedure above. Sand with 80 grade (grit) paper and remove sanding residue with Fiberglass Solvent Wash 202. Repair defects with Watertite, then sand and wipe clean. Apply Fiberglass Bottomkote ACT.

BARE WOOD: Sand with 80 grade (grit) sandpaper and remove sanding residue with Special Thinner 216. Repair defects with Watertite, then sand and wipe clean. Apply first coat reduced 10% with Special Thinner 216 or Brush-Ease 433. Fill seams, if necessary, with Seam Compound Brown 30. Apply 2 further coats of Fiberglass Bottomkote ACT.

PREVIOUSLY PAINTED SURFACES: In Good Condition: Wet sand surface with 80 grade (grit) paper to a clean firmly attached surface. Clean with Special Thinner 216. In Poor Condition: Use Interstrip to remove all traces of antifouling. Sand and wipe clean with Fibreglass Solvent Wash 202 for fiberglass and wood substrates. For steel, sandblast or grind to bright metal finish.

STEEL: Contact the Interlux Technical Service Department at 1-800-468-7589 for full information on how to properly prime underwater metals.

Method Apply a minimum of 2 coats (3 on bare wood) by brush, short-nap roller or spray. To prevent premature failure, ensure correct amount of paint is applied using the coverage as a guide.


Mixing Stir or shake contents thoroughly before use.

Thinner Special Thinner 216 or Brush-Ease 433.

Thinning Thin only if necessary. Thin no more than 10%. Use Brush-Ease 433 if roller or brush drags during application.

Cleaner Painted Surfaces - Special Thinner 216. Bare Fiberglass - Fiberglass Solvent Wash 202 or Fiberglass Surface Prep YMA601. Bare Wood - Special Thinner 216.

Airless Spray Tip Size: 0.53-0.66 mm/21-26 thou. Pressure: 170-204 bar/2500-3000 psi.

Conventional Spray Pressure Pot: Tip Size: 1.8-2.2 mm/70-85 thou. Pressure: 4.08-4.76 bar/60-70 psi (gun pressure); 10-15 psi (pot pressure).

Roller Use a 3/8" nap solvent resistant roller.

Other Take care to apply all the paint calculated even if it means applying an extra coat. Do not apply thin coats. Fill seams if necessary in between 1st and 2nd coats of antifouling with Underwater Seam Compound 30. Spraying of antifouling paints is prohibited in Canada.

Some Important Points Not suitable for use over aluminium/alloy substrates. Colors may fade or change above the waterline. Stir well before use. Product temperature should be minimum 10C/50F and maximum 29C/85F. Ambient temperature should be minimum 10C/50F and maximum 29C/85F. Substrate temperature should be minimum 10C/50F and maximum 29C/85F.

Compatibility/Substrates Not suitable for use over Aluminium/Alloy substrates. Suitable for fiberglass, wood and painted surfaces. Do not apply over tin-based copolymer antifouling paints. Do not use under vinyl based antifouling paints such as VC Offshore, Baltoplate or TBT based antifoulings such as Micron 33.

Number of Coats 2 coats, 3 on bare wood

Coverage (Theoretical) - 455 (sq. ft/Gal)

Recommended DFT 2.0 mils dry

Recommended WFT 3.5 mils wet

Application Methods Brush, Conventional Spray, Roller, Airless Spray

Interlux Fiberglass Bottomkote ACT with Slime Fighter specifications

  • Finish: Matte
  • Specific Gravity: 2.1
  • Volume Solids: 57%
  • Typical Shelf Life: 2 yrs
  • VOC (As Supplied): 370 g/lt
  • Unit Size: 1 US QUART, 1 US GALLON
  • Number of Coats:2-3 minimun, Bare Wood- 3 coats (first thinned)
  • Coverage:(Theoretical) - 455 (sq. ft./Gal)
  • Touch Dry Time: 50 F - 3 Hrs, 73 F - 2 Hrs, 95 F - 1 Hrs
  • Immersion Dry Time: 50 F - 16 Hrs, 73 F - 16 Hrs, 95 F - 16 Hrs


Drying Information  50 Degrees F  59 Degrees F  73 Degrees F  95 Degrees F 
Touch Dry (ISO)  3 hours  2 hours  1 hour  30 min 
Overcoating Info  Min-Max  Min-Max  Min-Max  Min-Max 
Time  16 hours  14 hours  12 hours   8 hours 

GENERAL INFORMATION: Exposure to air and extremes of temperature should be avoided. For the full shelf life of Fiberglass Bottomkote® ACT to be realised ensure that between use the container is firmly closed and the temperature is between 5°C/40°F and 35°C/95°F. Keep out of direct sunlight.

TRANSPORTATION: Fiberglass Bottomkote® ACT should be kept in securely closed containers during transport and storage.

GENERAL: Antifoulings should only be wet sanded. Never dry sand or burn-off old antifoulings. Read the label safety section for Health and Safety Information, also available from our Technical Help Line.

DISPOSAL: Do not discard tins or pour paint into water courses, use the facilities provided. It is best to allow paints to harden before disposal. Remainders of Fiberglass Bottomkote® ACT cannot be disposed of through the municipal waste route or dumped without permit. Disposal of remainders must be arranged for in consultation with the authorities.

BRAND: Interlux
Number Of Parts: One Part
Type: Copper AF Paint
4.1 17

I like the paint...good quality.


Unfortunately I give you NO stars as I did not get FREE shipping and no gown. That was for a my original paint equest you were out of stock. I purchased this one, but as a public service it would have been nice to offer the free shipping and paint gown and roller. It was offered on my original choice. I even had to pay more for this product.

Gary A.

Phillipston MA


Good Product at a Reasonable Price


I've used Interlux ACT for a number of years and it has always performed to specifications.I would caution that it should never be allowed to freeze. It seems that freezing can cause it to become lumpy and or muddy.

Boat Builder

Oyster Bay, NY


Would buy this again


Good product, covererage is great


Sandusky Ohio


Don't bother!


Without biocide this stuff sucks! Did not keep bottom clean for a month!


Chesapeake Bay


Went on easy and looks great.


I would buy this again


Chesapeake Bay




paint good price right...needs better shipping RE can was banged up causing leakage..


smithville NJ


Good price on a good paint.


I would buy from you again - JD is good to work with.

Jim Jam

Kinsale, VA







Good value multi-season paint


I used ACT on a 22' boat and got 4 years of life with 3 coats. Antifouling properties are good, had minimal cleaning at the end of the season. Just purchased more and I hope it does as well as the previous paint job. Jamestown had the best price and super fast delivery!




bait and switch


This is the product they advertise - but what you get is the new interlux product that is replacing Fiberglass Bottomkote ACT which is what I ordered. The 'new' product has about 1/2 of the copper as the old and 30% more 'inert' ingredients. I have yet to apply it to my Newport 30 but will write a review when I use it.


Harstine Island, WA

Interlux ACT Ablative Antifouling Bottom Paint



Related Items:
TotalBoat Blogs Live Tech Support