Hi! I posted in the forum last year right after we moved into our new home with a pool (never been a pool owner before). We had a bout with yellow algae, but brushed and shocked and increased our chlorine level and we didn't have any further problems for the rest of last summer. All winter, the pool stayed clear without any maintenance (except scooping out leaves and brushing occasionally). This year, it has stayed clear until we had a major hailstorm a few weeks ago. It was full of debris and turned green. So we brushed, shocked, vacuumed, etc. until it cleared up and it's been clear ever since. I'm using a Taylor K-2006 FAS-DPD test kit. Here are my most recent test results:
FC - 19.5-20.0 (not sure I trust my testing on this one)
CC - .5 or less
pH - 7.4
TA - 85
CH - 300
CYA - over 100 (reading was halfway between 100 mark and bottom of tube)
I did an overnight free chlorine loss test last night. At sundown, the FC was 19.5-20.0. This morning, the FC was 18. (I'm not completely confident in my reading of the FC. How "colorless" is "colorless"? )
Here is my question: Do I need to shock? The Chlorine/CYA chart gives a REALLY HIGH level of shock for my pool's CYA reading. How much bleach does that take? In the past when we've shocked, we just added the level of 'shock' powder
recommended on the box. It seemed to work ok.
Does everything else look ok? Should my chlorine level consistently be a lot higher? When we started getting the yellow algae this year, the chlorine was at about 10. After we shocked, it was up to 20, and it has remained there for the past few weeks. We use the chlorine tablets in an automatic chlorinator in the pump. I know this adds CYA, but I have a real problem getting my husband to buy into the liquid bleach idea. I'm still working on that.
Here are the details of my pool. (I'll add them to my signature next time I post.)
IG - approx 20,000 gal - plaster - Jandy 1.5HP - sand filter - installed 2003
We're newbie pool owners and I have no confidence at all in what I'm doing. I've gotten a lot of good info from this forum! Just looking for some input about my pool maintenance. Water looks clear almost all the time. We brush every couple of days, and vacuum and backwash probably every couple of weeks.