Hi folks. New to the forum, but I've spent the last couple of days reading posts from this forum, and it sounds like an incredible wealth of knowledge. Here is the background:
I just bought a house that came with a 20,000 gal Gunnite pool with a DE filter running Fiberclear. My estimate is that the pool is about 20 years old. The previous owner used Baquacil. But I recently converted to Chlorine. The gunnite is white, with lots of (brownish) stains all over the walls and bottom. At first, I just thought it was algae and then when my robot (polaris 9300) didn't pick any of it up, I went into "research mode." From what I can tell, they are most likely "metal stains." I'm not sure if they are copper or iron. I also have NO idea how long they have been there. I also have quite a few tannin stains from leaves and acorns, as my pool is SURROUNDED by trees. My water test results are below:
FAC: .05 (I know its low, I'm in final stages of converting from Baquacil)
Combine Chl: .45
Here is what I have done so far. I went to my local pool store and they gave me some "Stain free", which I was told was vitamin C. I added 1.75 lbs to the edge of the pool and to the steps, and didn't see a change at all in the color of the stains. At the time, I had very little chlorine in(refer to the levels above). My next thoughts are to do an Ascorbic Acid treatment with sequesterants based on the success stories on this forum. My question is that if the "vitamin c" treatment didn't help, would Ascorbic acid treatment do anything? Or do I just need to add more? Any ideas? I want
Thanks for taking the time out of your day to help!!