We recently installed a spool - a very small (about 1500 gallon) circular pool to allow us to get out of the heat in the Arizona summers. As I suppose is normal for new pool owners who have never had a pool before we are having problems maintaining water chemistry and those problems are probably more severe because the pool is so small. Our chlorine levels were so high that we had to cut our tablets in half not to drive up our chlorine levels.

We started using the pool about 3 or 4 weeks ago and, when I tested the water yesterday, I found very high CYA readings (> 150) as well as high (= 150) Total Alkalinity readings. I have read that the best way to get rid of high CYA is to drain and replace some of the water, but my real questions are (a) how did our readings get so high to begin with and (b) is high CYA dangerous to people. Our chlorine reading is also a bit high (about 5) but that may be low with such a high CYA reading.

The pool place near us recommended that we add muriatic acid to lower our Total Alkalinity but our pH is 7.6 and if I add the acid I assume I will also lower the pH. I guess I don't know how to get the values into a reasonable range to begin with so I can then try to maintain them.

Any suggestions? Thanks.