Gray Stains On My Fiberglass Pool
by Mike
Have developed a gray film on the inside walls, floor, steps. Have tried Stain Remover, Metal out, everything my local Pool Store, has recommended. Thanks for the question Mike First, I'd like to have your complete chemicals readings: Chlorine CYA (cyanuric acid/stabilizer) pH Alkalinity Calcium Hardness Metals (iron and copper) Total Dissolved Solids It makes troubleshooting much easier and the process of clearing up your pool will go much faster. You can get this done at your local pool store. Without these numbers I'm just guessing at what the problem is. I'd advise you to get a Taylor FAS-DPD K-2006 pool test kit. Pool Water Testing Water Testing Kit First, you need to determine whether the staining is either organic or mineral. Using a Trichlor tablet, hold it on the stain for about 10 minutes. Use a stick or a pool pole, not your finger. You can also use about 1/2 lb. of calcium hypochlorite (granular chlorine) in an old sock to put on a spot. If the stain doesn't lighten up, gets darker or the color changes to black, it's probably a metal stain. To confirm it's a metal stain, get a Vitamin C tablet (crushed up ascorbic acid), put that in a sock, and place it on the stain. If the stain is removed, you can treat the pool with ascorbic acid. For a complete ascorbic acid treatment go to this post: Brown Algae Won't Come Off Of A Vinyl Liner If it's metals, you'll need a good metal sequestrant. A metal sequestrant does not remove metal from pool water. It holds it in solution until it can get filtered. Then you backwash the metal out. Because metal sequestrants break down over time and get filtered and backwashed out, you need to weekly dose your pool if you have high iron and copper. Metal sequestrants that are based on HEDP, phosphonic acid or something similar are the most effective. Jack's Magic Blue, Purple, and Pink Pink Stuff, Metal Magic, Metal Free, & Metal Klear are very good. Be sure any algaecides you use don't have any metals or copper in them. You don't want to add to the problem. A good one is a PolyQuat 60. Remember that algaecides are for preventative measures, not to kill already existing algae. Hope this helps and let me know how it turns out for you. Robert |
