Max Chlorine PPM for Fiberglass Pools

[reneep]

I have a 10K gal fiberglass pool and have fought staining for several years with weekly shocking. Now that I have discovered this forum, I realize that using 3" tabs has caused my CYA level to be extremely high, causing the need for more CL, causing more staining. Now in the process of drain/refill to lower CYA and begin a bleach only plan. Having said all of that, the finish on the pool does not seem to have been affected.

[aylad]

reneep,

I don't think that the higher chlorine levels are causing your staining, unless it's because they are causing metals to precipitate out of the water. Have you had the water checked for metals?

Janet

[cajunfla]

reneep,

if your stains are a brownish-yellowish color, I found the answer in another thread here. I had those stains also, everywhere under the water, sides, steps. I was using tri-chlor tablets at that time. Put some vitamin C (ascorbic acid) tablets in a sock, and wet it. Then rub on a part of the stain. If the stain goes away, here is the fix. Buy some ascorbic acid in a powder form. The label may recommend some sort of 'metal free' also. I added the proper amount of each for my size pool, and the stains disappeared in minutes. It was the metals leaching out of the water and grabbing onto the pool. Has not returned yet. I have switched to the BBB method. Good 'ol hurricane Alberto added about 3 inches of water to my pool last night and today, so that will help lower the CYA level, as I had to drain some off.

[reneep]

I have had water tested many times (weekly), put way too many chemicals in the pool and spent WAY too much $$. Now I am trying to get it in shape and under control with the BBB method.

I am fighting very high CYA numbers. When I started the pool company reading was 192. I have drained about 4 inches of water off 3 times and purchased a drops test kit. Todays readings are listed below. Please give me guidance as to what to do. When I tested the CYA after the second refill it was down to 100. I have not tested after the third refill. I have had the pool for 6 years but have always just taken the water to the pool store and followed their directions so really, I am just learning to manage the chemicals. I have I think I may need to add bleach to raise the free clorine? The water looks and feels great. I do have a staining problem and will treat with stain out or something similar once I get the balance correct.

Thanks for you help. I have spent a lot of time reading and you guys do a great job of simplifying all of this and do not seem to tire of newbie questions. I am glad I found you!

CL 4
TA 170
Ph 7.6
Hardness 0