We bought our house last year and my project has been our pool. It seems I'm failing. I bought the test kit (TF-100) as suggested on this site and here are my readings:
FC - 0 (didn't even turn pink when I put the powder in)
CC - .5
PH - 7.5
TA - 120
CH - 170
CYA - 30
When we opened the pool this year, we had some yahoo do it. He incorrectly told us how to maintain a DE filter and we have since been doing it correctly. After backwashing and fixing the DE issue I was able to have a good chlorine level. It dropped off quickly and I have never been able to keep the chlorine level up. I had my husband try the backwashing trick again to no avail. The water has been clear and only slightly aqua at times, but a dose of chlorine (granular) it would go away. However, the bottom of the pool in the shallow end (where it becomes shaded quicker) has black spots (black algae?) I'm guessing algae is our problem with the chlorine (not sunlight) and I have not chlorinated it enough initially or correctly (bleach). Please help. I'm new to this but will follow your instructions and re-read and re-read all the Pool School stuff I need to. I really appreciate the help!