Ideal pump run time and SWG levels

[Drew80]

My pool is brand new as of last spring, and I'm finding it difficult to maintain my chlorine levels. It's about 8,500 gallons and my pump runs at about 60 GPM, so I'm running the pump for 4 hours per day. My CYA is currently at about 70. I have the SWG at 60%, and I'm still finding that the FC level is dropping by about 0.5 per day, give or take.

Does this sound about right, or am I doing something wrong?

 

[mknauss]

You are putting in about 1.9 ppm FC per day right now. Does seem odd you would be losing FC level with that addition at this time of year.
I assume you have a single speed pump?

I would suggest doing an Overnight Chlorine Loss Test some time soon. Add liquid chlorine to raise your FC to 10 ppm or so then check it the next morning before sunrise to see what FC loss you see.

 

[Drew80]

Yes, single speed pump. I'll do that tonight and report back.