CYA & Chlorine

[IMXTREEM2]

Split from here: cya-chlorine-t37065.html
It is always best to start your own thread when you have a question. Butterfly


Guys,

I'm having a similar issue with CYA. Although it was very high last year when we bought our house (May 2010), we went through the first summer on the BBB method and over time brought our CYA down to a desireable level. After the pool opening refill back in May 2011, large amounts of rainfall, and some refilling with the hose due to evaporation in the hot summer (plus normal splashout and a pesky drip now and again from the filter), the CYA now seems to be down somewhere below 20 (as tested by my TF-100 kit a few days ago. There's literally no amount of liquid that I add to that test tube that made the black dot fade out of sight). Granted it's been quite hot here in Chicago for the last few weeks, yesterday after work I added 2 of the "large" bottles of bleach from Wal-Mart and tested my FC in the morning. At that point, I was at about 11 or so (FC). After I got home from work today, I tested again and it was at MAYBE .5 (FC) if not 0. Under this, I'm spending $5/day on bleach and it's still not cutting it. I can only assume I need to raise my CYA, correct? Assuming my other levels are in check, what's the best way to approach this and, to what level should I bring it?

 

[frogabog]

Try adding 20ppm of CYA to the pool (HTH from walmart dissolves quite fast) in a sock hung by the return. Squish it frequently.

Without knowing your current level, adding 20 shouldn't put you above 40, and it should also give you enough to be able to test a registerable value for CYA. If you're still under 40 then, add more CYA to get to 40.

You can try to test for CYA within a few days after the sock is empty. Some of us have had accurate results the next day with the HTH stabilizer. YMMV as always, and testing a week after adding CYA is the standard recommendation.

 

[IMXTREEM2]

Thanks frogabog! I'll give that a shot this weekend!