Mold and mildew require moisture, food, a constant temperature, calm air and shade or darkness to grow and flourish. If you remove any, or preferably as many as possible of these prerequisites, you will eliminate your mold problem. The other problem is that if left unchecked, mold and mildew will penetrate the surface and in some cases the resulting stain is indelible and can not be removed. This is especially the case with vinyl seats. Using the right protectors will reduce the chance of permanent damage and make future cleaning much easier.
To solve your immediate problems, wash the fiberglass swim platform with Boat Clean Plus and water, using a scrub brush. While still wet, squirt some Boat Scrub on the swim platform and scrub again in all 6 directions. If any stains still remain, mix a 50/50 solution of Boat Clean Plus and Boat Scrub and scrub the areas that are stained until the stain is gone. Rinse well and dry or air dry in the sun. Boat manufacturers use these products to resolve warranty issues.
When the surface is dry, apply 2 coats of Sure Step. This will seal the pores in the gelcoat, leave a protective surface that will resist mold, protect against UV, put a nice shine on the platform and will give you some added traction, especially when the platform is wet. It will also make the swim platform much easier to clean.
To clean the seats, first spray EZ Vinyl Cleaner, full strength onto the mold and let stand for 10 to 15 minutes. Wet the seats with water and spray EZ Vinyl Cleaner, full strength onto the seats. Scrub the seats with a scrub brush to clean the indentations in the pattern and rinse clean. If stains still remain, scrub these areas with a 50/50 solution of EZ Vinyl Cleaner and Boat Scrub, until the stain is removed. If stains still remain, uncover the boat and let the sun get at the seats for a couple of weeks. Sun acts as natural bleach. If the stain still remains then they will have to be recovered. Chlorine bleach, aggressive solvents etc. will remove the stain but ruin the vinyl in the process, so you will have to recover.
When the seats are dry, apply 2 coats of Vinyl Guard. Vinyl Guard is not greasy or slippery and is a double barrier protection system. One part penetrates into the vinyl to restore the plasticizers and make the vinyl feel more luxurious. The second remains on the surface and protects your vinyl against mold staining, UV, suntan lotion, food spills and stains. In your area it will last about 3 months before you need to wash with EZ Vinyl Cleaner and re-apply.
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