Still having problems with CYA

[Andiejj]

Just tested:
Water clear
FC - 9.5
CC - 0
TC - 9.5
pH - 7.8
T/A - 90
CH - 270
CYA - 50
Temp - 93

Okay, over a 3 week period I have added 9 lbs of CYA (no backwashing nor filter cleaning). Why is my CYA not higher??? Any thoughts or suggestions? I have been trying to get my CL down this past week but running it much lower but not seeing much difference (went from 10.5 to 9.5). Any thoughts or suggestions would be great! Thanks

 

[JasonLion]

There have been several reports this season of stabalizer that either wasn't full strength or didn't have any CYA in it at all. It is possible that that is happening to you.

Also, keep in mind that it is important not to backwash/clean the filter for a week after adding CYA.

You should be able to turn down the percentage on your SWG and the FC level will come down over the next day or two. If it doesn't come down enough in three days turn the percentage down some more.

 

[Andiejj]

I have not backwashed nor cleaned filter since adding any of the CYA. So, guess I just have to add more of that costly CYA - UGH!

I usually run my SWG at 80%. Last thursday I think I turned it down to 50 or so then went out of town so left it at 60% for fri - sun. Tested Sun night and it was still holding at 10.5. Reduced it down to 25% for mon, tues and today yet when I tested late this afternoon it was only 9.5. SHould I reduce it even lower?

 

[chem geek]

If you have already used up your "CYA", remember that you can also add CYA by using Dichlor as your source of chlorine for a while. For every 1 ppm FC added by Dichlor, it also adds 0.9 ppm to CYA.