Cleaning painted Gelcoat

[frlrubett]

Previous owner painted my Mirage 28 with a 'good gelcoat paint from Marinesuperstore'. This has got the usual brown stains at the waterline, usually I use something like Oxalic Acid but do not want to remove the paint. Do you think this product would and is there an alternative which is a bit kinder?

Thanks!

 

[Stemar]

I used oxalic acid on my painted topsides for many years, but that was a two pack paint. It isn't a very strong acid, so I' be inclined to give it a go but, to quote the instructions on many a cleaner, try in an inconspicuous place first.