Adding stabilizer, how often?

[Kellyp]

I did a search but couldn't find an answer to my CYA query. CYA going up seems to be quite an issue for a lot of people, but does anyone struggle with it falling? I've been a student of TFP since I had the pool installed last May and I have not had the first issue with my pool. The CYA is not an issue, I just want to understand what's happening.

I added stabilizer a bit over 3 weeks ago to bring it to 70, tested today and its back to 50. CYA dropped consistently last year as well. I may have misunderstood, but thought I read that CYA doesn't really go away without replacing water, that it just becomes more concentrated as water evaporates. I've done a lot of CYA tests, so I'm pretty darn sure I do the test correctly, at any rate I do it consistently the same way. Its not an iffy thing either, I can quite clearly see the dot and pretty much exactly when it disappears. I am in GA, and it has been hot and sunny, so I am adding water at least once every week or two. I use well water that seems blessedly free from metals.

So, can anyone tell me if this is just normal and I simply need to test and adjust more often?
Current Chems:
Chl 6
PH 7.5
AlK 77
Cal 375
CYA 60 (after adding 1.5 lb early today)
Salt 3400

Fill Water:
Chlorine 0
PH 6.2
Alk 77
Calcium 75
CYA 0

Water is beautifully clear.

 

[mknauss]

CYA is lost to water overflow during rains, splash out, etc. It also is slowly oxidized at higher water temperatures. Above 85F seems to accelerate it some.

Normally if you test CYA every month during swim season you should be OK, unless a large rain event overflows the pool..

 

[Kellyp]

Ah, thank you for the clarification!