I am caring for an old pool, Parents 93, fired the pool service, shocked with diclor and brushed to rid of green algae then I found you. I have been using pucks to chlorinate but I will now change to liquid. Water is clear now, algae gone and test kit arrived yesterday. Readings today temp 68 f, FC 7, CC 0, Ch 725, TA190, CYA 150, fill water from hose PH 7.5, CH 400, TA 180. Used poolmath as best as I can figure out how to use it and it said replace 73% of pool water and I need to add 1 QT 2 cups MA. Pool drain is plugged I think and am presently digging up skimmer line looking for air leak. Have found and fixed 1 leak and can now use the auto pool vac and am able to keep pool clean. I would like your opinions and thoughts on this. Changing water will be a challenge.