madorh

I have new plaster pool (last fall), SWG never used then before close but was started up in May. 28,000 gal, DE filter, running 12 hrs/day. Was crystal clear at opening(and still is). initial store test showed: CYA 93, TC and FC 0, pH7,alkalinity 152 and total hardness 222. Shocking commenced...problem is can't maintain free chlorine. I have visited the pool store for testing roughly every 2-3 days, kept my ph and alkalinity ok, but now CYA is 151 after dumping all told 25 lbs. of stabilized shock (on pool stores recommendation... I was unsure if the SWG was working and Jandy was out yesterday - could not find a problem but replaced the cell anyway with new one. Even with SWG off, we dump 3-5 lbs. of shock in, FC is 5_10 on my strip or so, in 24 hrs. is down to 1.0 and in another 24 hrs. is 0.Store said to check phosphates - initially >500 and phosfree used. 2 days later was 100 in store, but Jandy's guy measured >1000 1day later! ?? AND FC 1agin after 24 hrs. of shocking.I have spent over $250 on shock and other chemicals. I drained the pool about 2 inches down but don't thinkg this will help CYA much(at least not according to your chart). I don't know if I need more phos free or not. Still can't maintain free chlorine, CYA level very high but have read different things on that and unsure if I should drain some more out. SHould I do bucket test now? Do I need to worry about CYA being so high? THe store has never even mentioned it as a problem - only found out by internet myself. I know now to use bleach instead of stabilized shock they sold me (25 lbs. of). SWG now at 100% since new cell put in last night and FC about 1 on strip this am. WHat would you suggest? I am getting test kit today too....