My test kit shows everything in my 25,000 gal vinyl linered pool, filtered w/a DE system right in the money. I primarily dose w/a half gallon of 6% liquid chlorine daily (buy it at Sam's in a 3 large-bottle pack totaling about 4 gallons for $7.79) with a 2# shock once a week of Ca Hypo & MPS alternately, and 10 oz of No Mor Problems mid week. This results in less than $50 a month for chemicals, $75 once a year for a Nature's 2 cartridge and water that is always crystal clear. On a whim, I took a sample to Leslie's & The Pool Warehouse just to confirm my results. Leslie's confirmed that everything was perfect, while The Pool Warehouse said my PH & alkanity were very high & phospates were through the roof at 1,000. Of course, they wanted to sell me a gallon of this & a gallon of that, etc.
Question: Anyone else have a similar experience with really different test results from various "free" water testing places?
Also, I think I can expect a gradual increase in PH with regular use of liquid chlorine, so would a periodic dose of acid be a good preventive strategy?