CYA level is too high

[slstrong]

I'm a new pool owner. We moved about 9 months ago and hired a pool service to maintain the pool. I decided to stop using the service a few weeks ago and maintain it myself. My Taylor K-2006 test kit came in the mail yesterday (yay!) and did a reading last night. Here are the numbers I got:

Ph - 7.6
TA - 90ppm
CH - 375
CYA - over 100
FC - 1.6

While I waited to get my K-2006 test kit in the mail, I was relying on test strips. The strips were telling me that my chlorine level was really high. I took the water to have it tested last week and both the FC and TC came back as high (5) as did the CYA (100). I turned off my chlorinator for 2 days and added soda ash to get the chlorine level down. I have since turned the chlorinator back on to it's lowest setting.

After reading about high CYA levels in the forum, I'm thinking my only option is to start draining water out of the pool. Auuughh!!

Your feedback is much appreciated!!!

 

[jblizzle]

Welcome to TFP!

Yes your CYA is much too high and will require draining and replacing water. Likely your FC was actually not high enough since pool stores do not understand the CYA/FC relationship. I am not sure where you got the idea that soda ash lowers FC all it actually does is raise the pH and TA some.

 

[Casey]

Welcome to TFP.

You unfortunately have to do partial drain/refills until you get the CYA down to a manageable number.

 

[Donldson]

Welcome to TFP!

You will need to replace a good portion of your water. Until you get your CYA in check you will need to keep your FC at appropriate levels for it. You should do a diluted test, where you mix half tap water with half pool water and use that to complete your CYA test. Double the number you come out with and that will give you a fair estimate of your actual CYA level. If your CYA level is, for an example, 150 you will need to maintain your FC level between 11-18. Use PoolMath to help you figure it out once you have a more accurate CYA number.

You didn't mention what your chlorinator is. Is it a puck feeder? If so then it is constantly adding CYA to your water and that is how those levels got there. Even after you bring your CYA in check continued use of pucks will cause your CYA to continue increasing, necessitating regular water replacement to keep it down. Something to keep in mind going forward, it might be worth looking in to alternatives to pucks for chlorination. I personally use liquid chlorine for my primary source and pucks occasionally, say for trips where I cannot add chlorine regularly.

 

[tim5055]

As someone who also inherited a pool with high CYA i feel for you and the position you are in. Donldson has already posted that you should do a diluted CYA test to try to get a handle on the exact CYA you are dealing with, so I'll skip that.

The K-2006 test kit will serve you well!!

I don't see your chlorinator in your signature, but I do see a ozonator. They are generally ineffective in outdoor residential pools. You can read more about ozone HERE.

 

[slstrong]

My chlorinator is a Rainbow Model 300/320 puck feeder...will add that to my signature line!!!

Thanks for the feedback!!!

 

[timerguy]

Continued use of the pucks will only ensure you will always have a high cya level that will become impossible to fix. Trust me, I inherited a pool that had nothing but pucks and dichlor shock for chlorine. I found my cya to be over 350 it took 44,000 gals of water to fix a 24,000 gal pool.