My pool is eaeating FC

[hortond]

Here are my current t numbers

FC 1
PH 7.6
TA 140
CYA 50

Water has been crystal clear and I am trying to keep FC near 7. The pool is in direct sunlight all day. I know that will eat FC. But this morning I tested the pool and my FC was 2. I put in 51 oz of Bleach. Tonight I checked it again and it was FC was down to 1. The water is crystal clear. No sign of any problems. What should I do to keep FC up?
Thanks

 

[Dstorm258]

I am by no means a pro, but if you are losing that much FC something may be eating it. Your best bet may be to balance your level of FC once the sun goes down and see if it drops still overnight (OCLT). If your FC level still drops with no sun, it means you may need to SLAM to kill what is eating your FC.

 

[pooldv]

Raise your FC up to 10 ppm, brush and retest in 15 minutes to see how fast it is dropping. If it drops below 7 repeat until it holds above 7. Then retest your CYA. And do an Overnight Chlorine Loss Test