Have to SLAM often to keep algae away...

[proavia]

@zea3 they get up to 6 inches of rain per month from may to Sep.. I doubt the auto fill even turns on for 6 months a year

The idea here is to see if there may be a leak in the pool. Shutting off the autofill and carefully measuring the pool water level and any possible rainfall will help determine if there is a leak.

Given the amount of stabilizer that has been added and the issues the OP is experiencing, this may help determine if there is a leak causing the issue.

 

[PoolBrews]

If there were a leak, I would expect the following to occur as well:

1. My Salt should drop accordingly as well. It has remained extremely steady at 3400 for over 5 months.
2. My water bill would increase significantly. It has been the same (give or take a couple of $$) over the past 6 months.

Even if there were a leak, I've kept my FC above 12, and my CYA at 60 or higher, so I shouldn't get a hazy pool.

 

[Katodude]

Do you have a main drain? Have you taken a hose with a concentrated nozzle down to it to try to clear it. Or better yet remove the cover to look?

Pictures, pictures, pictures.

 

[PoolBrews]

I have a main drain... looks clear. Pool is only 3 years old. I don't have a tool to remove the cover, and probably don't really want to try and do that.

In addition, every time I SLAM, I pass the OCLT after a day or two.

I have used 25lbs of dry Cyanuric acid in 15 months. Is that outrageous or normal?

 

[cowboycasey]

I bought 25 pounds 2 years ago and still have 10 pounds left

 

[Katodude]

The 25lbs is not outrageous. I did that in one year once.

I would try to get a hose down to the main drain and flush it out. And grab a bottle of LC cover the top and dump it down the main drain. Chlorine is a little heavier than water. Between the 2 you should kill everything down there. Not to say that is the problem, but we are looking at every little detail now.

 

[Newdude]

The 25lbs is not outrageous

+1. You guys have had something like 70 inches of rain over the 15 months in question. You average 51 inches a year and this one was wet.

 

[zea3]

Yes I wanted to check if an undetected leak was causing you to use so much CYA, but we've ruled that out now. However if tons of rain are the cause of the CYA loss then there also should have been a corresponding drop in salt. Do you check salt each time you check CYA?