Biokleen M00609 Fiberglass Cleaner Gallon, 1 Count (Pack of 1)

Have used this product now for 6 years. Breaks down and removes the algae layer without damaging the fiberglass and paint.

Can definitely say I'm a fan of this product I have ordered it in the small version and now in the large one gallon and I use this for a lot of different boating tasks objectives does a great job of cleaning.

Does great job of removing yellowing stains from hull of boat. Just spray it on and hose it off!

This works wonders on my older fiberglass shower stall. As this type of shower gets old, it can be difficult to get it clean. This product is the only thing that has worked on our shower stall. We were considering replacing our shower stall but, thanks to this product, we won't have to for quite a while. As with any strong cleaner, you should be careful to have adequate ventilation. This one is pretty fumey!

Excellent product, very good for cleaning ships, bathtubs, etc. I recommend it.

Purchased to clean fiberglass rv roof before resealing. This cleaner is very effective and fast acting with little effort required. Very happy with results. Little goes a long ways. One spray bottle cleaned entire 40’ rv roof. Wear gloves it may irritate skin.

This works great on boats. We are in an area with a lot of hard water in the lakes. Some boats will look they have a lot of oxidation but it is just a build up of the water spots. This takes that layer right off.

Wow, I couldn't believe how the layers of mineral deposits, grime, mold, and oxidation that built up since the middle 1980s disappeared and the fiberglass now has the original luster that was lost over all the years. We unsuccessfully tried mineral deposit cleaners, bleach, etc., and what they did was superficial. You may have to apply this product more than once to get ancient stains up, but it is worth it. Wow!!!!!!!!!!!

This stuff works surprisingly well. I can’t cover my Motorhome every winter so in spring there are black dots all over the fibreglass gel coat. This stuff took all that mold mildew off very easily.

This product is excellent.

Works OK. I compared it to Pine-Sol and I thought the Pine-Sol did a slightly better job. I don’t think I would buy this again and would just use Pine-Sol on my RV next time.

It does not clean older fibreglass boats save your money

Seems to depend what type of surface you put it on. On our fiberglass boat which sits in the water all summer, it helped to apply to dry hull and let sit for a few minutes, agitate and re-apply. I found at least a couple of applications were necessary. Another product I used last year was more expensive but tended to eat away the scum faster and easier. Having said that, when applied to my aluminum boat hull it worked extremely well. I would guess the scum on that hull had been there for at least a couple of years, and within less than a minute you could almost wipe the grime off. Didn't seem to hurt the white paint on other parts of this hull when I applied there. Only giving 3 stars as I bought this mainly for our fiberglass hull and other products work better, but it does work, just requires more work and also used about 1/2-2/3's of the bottle for 18 foot boat. I will use the rest to clean the rest of the aluminum boat and try it on our RV/trailer next year.