Quote Originally Posted by illinipdx
Thanks Waterbear,

I'm not sure what order to go do things in now. Yesterday I posted our numbers in the "Testing and adjusting pool chemistry" section. There is also staining everywhere, and it responds to vitamin C, so it looks like we have metals. Here are the numbers.

Fc: 14.8
CC: 2.2
PH: below lowest level (when we did the Base demand test we needed 95 drops)
CYA: >100 (since 100 is the first mark, we are guessing ~110)
TA: 30-40

At first I thought we should get the PH up, but maybe we should only get it up a bit, get the chlorine down to 0, and get the stains out first. What do you think?

I don't think I can convince my parents to drain to get the CYA down, at least not yet. Is this high CYA possibly the result of using stabilized chlorine?

Thanks!
You need to get the CYA down first. The high CYA is the result of using staiblized chlorine...no possibly about it! The low pH is also from the trichlor tabs...they are very acidic! I hope you do not have a vinyl pool because you are ruining the liner with the low pH (not so great for plaster either!)

CYA can't be accurately measured above about 90 ppm so I would dilute a water sample with an equal part of distilled water and test that then multiply the results by 2.

The first thing I would do is use soda ash to raise both your pH and TA to protect the finish of your pool...Then I would drain and refill to get the CYA down to 30-50 ppm.
Once that is done you can attack the stains. You need to let the chlorine level drop to 1 ppm and get the pH down to about 7.2 before using the ascorbic acid...filter for an hour and then add 1 bottle of seqesterant like Jack's Magic or Metal Magic per 10000 gallons and filter for 24-48 hours until the staining is gone. Then raise your FC with bleach poured into the skimmer 1 ppm per day until the FC is holding (the ascorbic acid will destroy it at first) and then bring it up to about 5 ppm (1 ppm increase per day!)
DO NOT SHOCK THE POOL FOR 2 WEEKS or you risk the staining coming back.
Hope this helps.