I recently started a business servicing pools. I was called to a green pool, tested it and found these results:
pH - 7.8 FC - 0, TDS 1200, Cyanuric Acid 180...
So I figured that high cyanuric acid was locking out any chlorine, and surely the only way to lower CA is to dilute it? Same for TDS?
Anyway, I balanced the pH to 7.4, and after dumping about 2 thirds of the total water over the course of a week (as recommended by the pool calculator), the pool cleared up - job done, or so I thought - This was a week ago.
So today, I got an email asking for a partial refund - apparently their pool had gone green again, and they called someone else out who cleared the pool in 3 hours!
What the **** did he do? Or what have I missed?
I am still new to being in the business, and I don't know everything. Never heard of a pool going from green to clear that quickly. Is this some industry secret that I don't know about? What did I do wrong?