How to get started with CYA

[Danie Dee]

Hello, I bought a place with a pool about 3 yrs ago. It came with the old testing sets I grew up with that just test chlorine and acid. I test those two and end up adding a about a half gallon of chlorine every other week and about 6 cups of muriatic acid every other week and the levels are maintained. After talking with a friend who is a pool owner and loves this site, he convinced me that I should not be adding the muriatic acid so often, that there is something wrong if the water is getting so acidic so often. He told me about CYA and considering that I live in Tucson, that seems important. He also said that the acidity might be damaging the plaster.

So I guess I have two questions.
1. Could someone please recommend a testing kit that tests CYA and a brand to add the chemical?
2. Also does anyone know why my pool would be getting so acidic and if adding so much muriatic acid is harmful to the plaster?

MUCHAS GRACIAS

 

[Mdragger88]

Taylor k2006c (available at various online retailers)
or tf100/tfpro from tftestkits.net
are the only kits recommended
Test Kits Compared
Read Pool Care Basics
It is not unusual to need to add acid often in your area.
The amount & frequency of chlorine you’re adding seems quite low to keep a sanitary pool.

 

[Texas Splash]

DD, welcome to TFP! I'll note a few things as well:
1- Your water is expected to be hard. Evaporation requires more top-offs, so the Calcium Hardness level is a challenge for many AZ pool owners. For that reason. it is very important to manage your pH level. PH will determine if the water, which is probably over-saturated with calcium, will try to fall out of solution and grab the pool surfaces (scale), or if the calcium will be maintained in check. In short, 4 things determine the likelihood of your pool developing scale: CH (not easily changed), water temp (it is what it is), TA (we have some flexibility), and pH (the biggest influencer).

The other side of the coin is preventing algae, and that comes down to FC and CYA. See our FC/CYA Levels for how those two should be balanced together. If you have been using tablets, then your CYA is probably too high. Liquid chlorine is generally the best option.

But get one of those test kit and post back with your numbers. We'll coach you from there.