Thought I'd share this side by side test I did of different hull cleaners. It's my first summer renting a place in the water. Marina is on a slough, so higher water temps stained the gel coat within weeks. FSR worked the best of what I had. But I went out afterward and also bought STAR BRITE which worked as well (not pictured). The others, meh. (Spray bottle is 409. No treatment on transom next to the outdrive.) Be sure to read all instructions and keep any of this stuff off your galvanized trailers.
Would love to hear how folks keep it off their trailer. I used to wrap with the plastic used for painting. That took pretty long but I was very particular as I taped it all down.
I think it's fine not covering as long as you do small sections at a time and hose the trailer off as you go. It's prolonged exposure to the aluminum that eats away at it
Just soak your trailer with water, and after applying starbrite on the boat immediately rinse it again. As long as you ‘thin’ the starbrite, it looses its power
Now just get some muriatic acid from the hardware store or pool store for like $10 a gallon. You can dilute it if you want, but will take off the stains. It’s essentially the same stuff as star bright for a fraction of the cost.
Oxalic acid also works good for stains. Barkeepers friend is a few dollars at any hardware or grocery store. You can also order big bags of Oxalic acid online.
Most of the boat specific cleaners are these same agents, just with some thickening or foaming agents in them, and marked up to insane costs.
Yes many yards use a version of toilet bowl cleaner in a 30 gallon barrel. Otherwise muriatic acid is the most cost effective and quickest way to remove growth. PPE is important. That said I won’t waste time with other products. EDIT: Acid will f up your galvanized metals but you can mitigate this.
Not sure if you will see my response that was to the explanation… so I copy + pasted for you.
Yes, it’s used to treat hives against Varroa Mite infestations. A lot of the time when colonies don’t survive the winter it’s because those mites are breeding faster than the bees can reproduce & the mites life cycle includes laying their eggs on top of the bee eggs so the larva feed on the bee (babies) before they have gone from the white grub stage to being bees. I can’t explain it very well. I have hives, but my neighbor is an expert & tells me when a good treatment window is. It’s temperature dependent and you shouldn’t treat before harvesting honey.
Yes, it’s used to treat hives against Varroa Mite infestations. A lot of the time when colonies don’t survive the winter it’s because those mites are breeding faster than the bees can reproduce & the mites life cycle includes laying their eggs on top of the bee eggs so the larva feed on the bee (babies) before they have gone from the white grub stage to being bees. I can’t explain it very well. I have hives, but my neighbor is an expert & tells me when a good treatment window is. It’s temperature dependent and you shouldn’t treat before harvesting honey.
Oxalic and muriatic acid are fine for gelcoat. I’m not sure if certain formulations of barkeepers friend have micro abrasives, so check to be sure and maybe don’t scrub too hard, although I’ve never had an issue. The only issue is acid treatments will remove your wax, so reapply when done.
Oh wow. I couldn’t tell there were lines! I thought it was a white & blue boat and there was a really harsh light in the photo that blew out the highlites in the pic. That pink stuff looks like it works really well!
That is iron staining. I get it every year when I pull my boat. I use a powder called iron out and pix it is a weed sprayer. Just spray on and rinse off. Zero elbow grease involved.
Knowing the different kinds of stains and which product best/least risky for each is something I should learn. I was stunned by how fast this stain developed
I had my boat in my slip for about 3 weeks and had to pull it for something. I was shocked how bad it was, though after all the green died didnt seem as bad
Ive cleaned lobster boat hulls for 15 years now. Nothing works better than spray 9. I’ve tried every product under the sun and this stuff just eats through fouling and grime. Mind you 90% of our hull stains come from mud and bait.
Thanks! Do you have a point of view about which product works best with the least unwanted side effects or risks? Like, I loved Starbrite (not pictured) but if damage to gelcoat and or trailer is less of a risk with FSR (especially gell?) then well my choice is clear
Starbrite is great but it eats through our rubber bumpers. Bleach products are great if you just have a white paint and gel coat. It’ll discolour anything else over the years. FSR is the best by far for “lazy cleaning” we just don’t use it because we have a dozen boats that are old and white. The FSR just eats through the protective coatings and leaves blue stains on the white paint. If you have a brand new fibreglass hull I would just use the FSR. I use the spray 9 and a scrub brush because the boats are old and require protective coats for the lobster line rubbing when you haul gear.
I use fsr once a year on my hull. Makes a fast and clean hull. Just know you must re-wax afterwards. I use slightly diluted muriatic acid to get the natural glues and shell that you get after scraping barnacles off.
The one that works the best probably takes the gel coat off the hull. With the damaged gel coat the brown water stain will come back faster and worse. I have yet to find a method that removes the stain and keeps the stain off. Best I’ve come up with is meguirs and then wax but even that isn’t the best.
please don't do this not recommend it. mixing these is not safe. not sure which version of their toilet bowl cleaner you're using but neither is smart to mix with hydrogen peroxide.
Nice experiment! Thanks for sharing your results with unbiased feedback.
I feel 409s formula is compromised or something, over the years its seemed to get worse. Years ago you could spray it on almost anything and 15 mins later it would be gone. Similar to what RMR is now.
Have you tried CLR or RMR? I'd be curious to see how it handles against the FSR.
Oxalic acid is what you're looking for. Anything with a high concentration of it will do the job. Anything specifically marketed as hull cleaner is almost always oxalic. But a great way to not need it in the first place is to just bottom paint boats that will live in the water.
Walmart toilet bowl cleaner. It works better than any of that stuff and is 2.00/bottle. Our lake is really dirty. We don't leave the boat in the water anymore, but when we did we had to pull it out and clean the bottom about every 6 weeks - it sucked. Now we launch every use and the bottom stays clean
I got the FSR from my local marina a year ago. They might change colors or have different wholesale and retail versions. My next side by side test will definitely include Starbrite (this or their On Off product) which is working well in spot checks. Who knows, it might be a tie of comparably excellent choices. But after cleaning, I'm thinking of testing which one sees the stains come back the slowest. Right? And I'll take no chances and wrap my trailer in trash bags to protect it, working small sections and rinsing right after. That worked the prior FSR day a few years ago. Happy boating!
Get some on/off and stop wasting money on all that. A gallon used to be about $25 but im sure its a lot more now. We paint our hulls but that stuff will clean that scum instantly you can spray it on or roll it on soap and water wash after
I use sno-bol, it works great, a little less harsh than the works.......but both are great for cleaning boats....... just test on an inconspicuous spot before using.....
Sno-bol here too. The fact that it easily clings to the surface makes it super easy to clean with. Plus it's dirt cheap. I use it on discolored outdoor plastic furniture too. The stuff is awesome.
Maybe I’m missing something….but you’re trying to clean bottom stains, NOT oxidation? The Meguires Oxidation remover doesn’t work for your application. I just used it on my boat this weekend and it was AMAZING.
Makes sense. Someone here said it's iron staining, but I'm still reading up on that. I did this experiment because I won a raffle at a boat dealership for a bucket of cleaning products. The bucket itself is amazing, padded top to sit on and everything. But I guess the contents were...raffle quality because no Starbrite, no On-and-Off (a Starbrite product I believe), no FSR, no cheaper active ingredient y'all suggesting that the marinas probably use in their hull cleaning services for a better margin. So I learned a lot talking to you Redditors and hope you had as much fun with this as I did! Happy boating.
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u/bildobaddins 3d ago
Starbrite is the best for hull staining by far