Can't keep chlorine in my pool

[W@terbug]

I need a little help from the pool pros I am a new pool owner and don't have a lot of experience. My water is beautiful crystal clear I ran a set of tests with my taylor k2006 kit and got the following numbers.

FC 2.5
CC 0
Ph 7.6
TA 110
CYA. 50

I have been having a hard time keeping the chlorine up. At the end of last week I thought I might have a problem with organics because of my chlorine loss so I started a shock process. After 2 days of keeping the chlorine up, I was able to pass the overnight chlorine test. Yesterday I let the chlorine go and did another overnight test into this morning last night after the sun set my FC was at 8.5 and 0 CC this morning before the sun hit the pool it was at 7.5 with 0 CC. Now I am at 2.5 with 0 CC and I still have a few hours of sunlight to go? Am I missing something obvious? Is this normal to have this kind of chlorine loss every day? Unless I add chlorine twice a day it is proving impossible to keep it between the recommended 3-6 range. At this rate I will use about 3/4 of a gallon of 12.5% chlorine every day. My pool gets 100% full sun and it has been very sunny and hot. the pool is a 24 foot round AG pool with 1.5 Hp hayward 150 lb sand filter. anyone have any advise?

[Watermom]

If you are having this much trouble keeping chlorine in your pool, you may want to bump your CYA level up some. Maybe try taking it up to 60 and see if that works better for you.

On an unrelated note ------ It is going to be very important for you to try and keep your pool from getting algae. You have a mismatch between the pump and filter size which we often see on AG pools. In the case of pool pumps, bigger is not always better. When you have a too large pump paired with a too small filter like you do, you often don't get very good filtration. The too powerful pump forces the debris through the sand bed and back into the pump. If you have algae that is being filtered, the force often breaks the algae into even smaller pieces which makes it almost impossible to filter out. So, you want to make sure you never get algae. And, when it is time to replace the equipment, you want to have it sized up better for your pool.

(To give you an example --- I used to have a 24ft AG. When my pump died and I needed a new one, I had one of the other moderators (username Poconos, although he is no longer active on the forum) pick out what I should buy. I got a full-rated 1/2 hp inground pump. (Inground pumps are usually made a little better than AG ones.) It was paired with my 300lb. sand filter. This combo worked well -- smaller pump, larger filter. I am still using that same setup with the pool that I have now that is a 27ft AG about 17K-18K gallons of water.) Just an FYI.

Welcome to the Pool Forum, by the way!

[W@terbug]

Not 100% sure of the CYA. I wish there was a better way to test than the black dot. it is so hard to be sure. Does water temp and hot weather affect the rate of chlorine burn or just uv? I am wondering if it could just be high because the heat wave we have had. I would hate to bump the CYA if at all possible. Wondering if the weather cooled off a little or had a day with some clouds if it would slow down. Also was wondering if the bond between CYA and chlorine was instant? i guess i am wondering if it might need a little extra for a few nights for the stabilizer have enough to do its job then it might slow in a few days? I would think it would be fairly quick but I don't really know enough about this yet.