It's bold packaging boasts an equally bold claim. Does Grunt really have the grunt needed to make my old Rustler 31 sparkle again? To avoid unnecessary suspense and anguish. Yes it does.

Product Overview

Overall rating:


Grunt Boat Cleaner


  • easy to use, versatile, does the job, made with biodegradable formula


  • painting on requires a little bit of paintbrush faffing and cleaning


I tried Grunt boat cleaner and my boat has never looked so clean!

Grunt Boat Cleaner

Comes in 500ml and 1 litre bottles
Suitable for use on fiberglass, gel coat, metal, and painted surfaces
Can be applied using a spray bottle or brush
Contains biodegradable ingredients

A little bit goes a long way. I’ve been using Grunt cleaner on a project boat that was absolutely filthy inside and out.
Simply pour a bit o Grunt into a container and using a paint brush, daub it neat onto any surface for a deep clean. Leave it for a few minutes and wipe or sponge  it away. Surfaces come up clean and visibly stain removed. Some stubborn stains have needed a few extra sessions with the cleaner to make them fade away.

It’s recommended that you wear gloves and eye protection. Typically I am that luddite that wears neither. So far no harm has been done to my skin when I’ve accidentally got it on me and wiped it straight off. It states clearly on the packaging that it could be a skin irritant though so user beware, use gloves if you’re going to be getting it on your hands.

It effortlessly removes stubborn stains, algae buildup, and grime from various boat surfaces, including fiberglass, gel coat, metal, and painted surfaces. Whether you’re dealing with waterline stains, oxidation, or general dirt accumulation, Grunt can handle it all.

Grunt Boat Cleaner is formulated using biodegradable ingredients. This makes it a safer choice for use in marine environments than many of the other toxic hazards we use to clean boats.

A little goes a long way too.

Overall, I really like Grunt Boat Cleaner and recommend it as a go-to product for a multitude of cleaning jobs. Its powerful cleaning action, versatility, ease of use, and environmentally friendly formulation make it my top choice of cleaner.

Buy it now

Before using Grunt cleaner

After using Grunt cleaner