I have a 29,000 gallon swg pool. Having trouble holding chlorine level and CYA level seems to have dropped from 50 to 10 in 2 weeks. I had this issue a month or so ago and appeared to solve the problem but now here I am again. I am in Omaha, ne where we have had a few stretches of 95+ temp weeks with a cool week last week. Also a couple 2-4 inch rains in there. I have cartridge filters so do not normally remove water, but had to remove a couple inches twice. I have an in floor cleaning system and there is a strange off white to light brown film like substance turning up in the canister from floor drain. Pool has been very clear and no evidence of any algae in pool or in any other components of the system. the last two weeks but I have to run chlorinator at 100% way more than the normal 12 run time at 80% I have run it for last 2 years. I'm at a loss. Please help.Thanks
reading 6/24
TC. 2.5
FC. 2.5
ph. 7.5
alkal. 110
calc hard. 100
cya. 45
readings 07/08
TC. .2
FC. .0
ph. 7.4
alkal. 105
calc hard. 100
CYA. 10
reading 6/24
TC. 2.5
FC. 2.5
ph. 7.5
alkal. 110
calc hard. 100
cya. 45
readings 07/08
TC. .2
FC. .0
ph. 7.4
alkal. 105
calc hard. 100
CYA. 10