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Interlux
Interlux Fiberglass Bottomkote NT Antifouling Paint
Item: #870500 | Part Number: Not Selected$48.99 - $135.99
Description
- Dual-resin formula combines hard paint durability with ablative polishing
- Fast-dry for same-day painting and launching
- Universal use on fiberglass, wood, and primed metals (except aluminum)
- Effective in fresh, salt, and brackish waters
Interlux Fiberglass Bottomkote NT Antifouling Paint Item # 870500
Description
Fiberglass Bottomkote NT uses a dual resin technology that provides a universal durable, fast dry antifouling paint that delivers the benefits of both hard and ablative antifouling paints for use on all power and sailboats. Fiberglass Bottomkote NT can be applied over most other antifouling paints provided the old coating is tightly adhered and is in sound condition. Always refer to the Interlux antifouling compatibility chart for overcoating recommendations.
Features:
- The universal formula of Fiberglass Bottomkote NT has durability of a traditional hard paint but has a slow polishing mechanism built-in that continuously smoothes and renews the active surface avoiding the heavy buildup of paint layers much like an ablative paint
- The fast dry formula allows the boat to be painted and launched in the same day
- Fiberglass Bottomkote NT provides clean stable colors for effective season-long protection
- Fiberglass Bottomkote NT is recommended for use on the underwater areas of fiberglass, wood, and properly primed metal (except aluminum) boat hulls
- It can be used in fresh, salt and brackish waters
- Suitable for below the waterline only
The Fiberglass Bottomkote NT Advantages:
- NT (New Technology): Optimizes the benefits of hard and ablative paints through a unique Dual Resin approach
- Durable: Coating prevents premature wear-through yet a slow polishing action minimizes unnecessary paint buildup
- Renewable: Surface continuously smooths with use, providing a fast, fuel efficient coating
- Fast dry: With (2) hours between coats and (6) hours to launch at 75ºF, this super fast formula offers productivity benefits for both yards & Do-It-Yourself applicators
- Universal: A cost effective choice for all power and sail boats and in all waters
Specifications:
- Color Code:
- Red = YBB349
- Green = YBB359
- Blue = YBB369
- Black = YBB379
- Coverage: 400 sq. ft./Gal. Yields 2 mils dry film thickness
- Surfaces: Fiberglass, wood and properly primed metals. Do not use on aluminum
- Application Methods: Brush, roller or airless spray
- Application Temperature: 50°F (10°C) and above
- Dry Times at 75°F
- Touch dry – 1 hours
- Dry to overcoat – 2 hours
- Dry to launch – 6 hours
- Coats Required: (2) coats minimum at 4 mils WFT/2 mils DFT
- VOC: Less than 465 g/L Less than 3.9 lbs/Gal
- Water-Based: No
- Components: 1
Note: Please consult the Interlux Paint Estimator to determine how much paint you will need.
Part Numbers for Interlux Fiberglass Bottomkote NT Antifouling Paint
Reviews
Rated 1 out of
5
by
SailorJoe from
Sailors, ye be warned!
We are world cruisers and have hauled out five times, using a variety of antifouling products depending on availability. This isn’t our first rodeo. Unfortunately, Interlux Bottomkote is by far the worst product we’ve ever used.
It was recommended by Budget Marine in Grenada when we hauled out there to paint the bottom. The product was described as both hard and ablative, but I can tell you there’s nothing hard about it. We had hoped it would at least fend off growth for a single Caribbean season, but we were gutted to see growth forming after just one week in Prickly Bay. By the time we reached Sint Maarten, our undercarriage was already sporting the dreaded green beard.
In our experience, this product is clearly inferior, and we wouldn’t recommend it to any scurvy sea dog.
Date published: 2026-03-10
Rated 5 out of
5
by
Captan Jake from
Great paint and great price.
I was reluctant to use this paint because of the low price but it has performed great. This is my third purchase over four years for my Cal 35. Located in central Florida on the intercostal.
Date published: 2025-11-24
Rated 4 out of
5
by
Evan from
Good paint/Shipping not so much
The paint goes on well & I have been using it for many years. Usually buy it in person but had it shipped this year and although the packaging looked to be secure and in good shape the paint can looked like it had been tumbled around in a clothes dryer…. Was surprised it was still intact and not leaking
Date published: 2025-08-11
Rated 5 out of
5
by
Robbie from
Great product
Excellent summertime protection against growth and slime.
Date published: 2025-01-29
Rated 5 out of
5
by
DBC125 from
Just right
This is excellent bottom paint, I get 2 coats per gallon on my 26ft sailboat.
Date published: 2024-07-19
Rated 5 out of
5
by
Don'tbeajerk from
Stands up to cruising speed
easy to apply-works well. Takes a licking and keeps ticking!
Date published: 2024-07-19
Rated 2 out of
5
by
Bobby from
Good product, bad shipping
Overall the product itself was very good. Unfortunately I ordered 2 gallons that came in a single box with each gallon in a separate zipper plastic bag. Although the box looked ok, both cans were damaged and one had opened.
Date published: 2024-07-18
Rated 5 out of
5
by
D*** from
Effective
Have used it for years on 66 year old Lyman. Consistent results
Date published: 2024-06-18
Questions
What is the copper percent
The copper content is 75%
Date published: 2024-07-31
Can you put this over a epoxy primer
THIS IS WHAT GROK says regarding epoxy:
Yes, you can use an epoxy primer before applying ablative bottom paint, but there are important considerations to ensure compatibility and proper adhesion:
Compatibility: Most ablative antifouling paints are compatible with epoxy primers, but you must verify this with the paint manufacturer’s guidelines. For example, brands like Interlux and Pettit often specify compatible primers in their product data sheets. Ensure the epoxy primer is designed for marine use and suitable for the ablative paint you plan to apply.
Surface Preparation: The epoxy primer must be properly applied to a clean, sanded, and dry hull surface. After the epoxy primer cures (per manufacturer instructions, typically 24–48 hours), lightly sand it (e.g., with 80–120 grit sandpaper) to create a surface for the ablative paint to adhere to.
Application: Apply the ablative paint within the primer’s recommended overcoating window (check the primer’s technical data sheet). If the window is missed, additional sanding may be required. Follow the ablative paint manufacturer’s instructions for the number of coats, typically 2–3 for optimal protection.
Benefits of Epoxy Primer: Using an epoxy primer creates a strong barrier coat, protecting the hull from water intrusion and improving adhesion for the ablative paint, especially on bare fiberglass or metal hulls.
Date published: 2025-10-13
Is it recommended to thin Interlux Bottomkote NT? If so what should be used?
Stated in Technical Data Sheet on Interlux site.
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.
Clean Up Special Thinner 216 or Brush-Ease 433.
Date published: 2024-04-09
Is this a multi season product?
The Bottomkote is ablative - it wears away taking fouling agents with it. I prep the surface and apply new Bottomkote every year, usually in April. The boat is a 1958 wood lap strake.
Date published: 2026-03-20