I'm a newbee to this forum- never been a member of any forum, so I hope this question is not a repeat. I'm also a new pool owner and trying to maintain it myself. Because I bought a house with a 20 year old pool, I found some issues with the pool- had trouble with algae and cloudiness. The local pool expert advised me to shock the pool with dichlor and never to use Cal Hypo or bleach. After 2 shocks of dichlor and some liquid bleach, the green turned to cloudy blue, so the expert then advised a flock, which did the trick. Crystal clear water. After a couple of weeks of good water (and high chlorine levels), I started noticing a little cloudiness and a green-brown scum forming on some of the seams (vinyl liner). After reading this forum, I suspected that my real problem was high CYA so I bought a Taylor test kit and found CYA off the chart (used distilled water to cut my pool water) and think the CYA was 150. Said expert advised me to shock with dichlor again to get rid of the cloudiness, then drain half the pool. I protested that dichlor would add CYA, which I am trying to correct. He assured me dichlor does not have CYA. I used liquid bleach instead, thinking that it was probably futile anyway until I got rid of the extra CYA. So I drained more than half the pool, refilled and got CYA to 60, and now I need to shock and re-balance. First question: does dichlor have CYA? It would seem like a very bad choice for my pool if it does. We have very low calcium in our tap water- I measured 0 calcium hardness in our tap water, and after refilling the pool, measured 40. Second question: with the vinyl liner, do I still need to try to get to 200 ppm calcium hardness? Third question, I've read that adding calcium can cause cloudiness- is that true if my CH is only 40? With the low CH, does it make sense to go ahead and use cal hypo for shock and to maintain FC until CH gets higher, then switch to liquid chlorine? Or should I just use liquid bleach and increase CH with Calcium Chloride? Which method will give less cloudiness?