FC = 4.5
CC = < .5
Ph = 7.5
Alk = 150
So things are looking much better with my pool this year. Last year I had a CYA of 120 (yikes!) and a partial refill during the winter closing did the trick.
I feel I have a good grasp on what I'm doing now. My water has never looked better I've even trained another person on using the BBB method and finding that training others really reinforces what I've learned here. A big thank you to everybody!
That said I do have a few questions:
1. My current usage is about one gallon of 12.5% bleach a day which I buy from the pool store for $11.30 for a case of four. With tax that's roughly $3 a bottle. So that's $90 a month ($450 for five months) in chemical usage to run the pool and I'm wondering if that's good, bad or indifferent compared to others with a similar pool size (25k gallons)? This does not include any extra I'd need if I have to shock again.
2. My plan is to get my CYA to 30 by using some pucks. Should I test daily, weekly, bi-weekly for CYA? ie... how long will it take for pucks to move my pool from 20 to 30? and when I say 20 I'm guessing because I fill the entire tube up and can still see the black dot. However I only drained half the pool last year with a cya of 120 so there should be still some in there.
3. I understand the cya chlorine relationship, but if somebody has a high CYA and requires a higher range of bleach, I've read on TFP that it is safe to swim in all the way up to shock level, which could be 39ppm in some instances where cya is over 100. Is this still true and how can it not hurt you at that level? I'm asking as that was one answer I didn't know how to explain to somebody.
4. Being I have a sand filter I wanted to see what adding DE would do for me. With my water clear, I followed the procedure here: http://www.troublefreepool.com/pool-..._a_sand_filter and at first was able to get two cups in. About 3 hours later the heater turned off from low pressure and the pump was working hard so I did a backwash and noticed quite a bit of dirty water. So I lowered it down to one cup and it did about the same this time but not as much dirt. So I went down to 1/4 cup and it did the same after about 5 hours again without much visible dirt during the backwash. So my question is am I doing this right? I changed my sand out this year, inspected my laterals and refilled with new pool grade sand so I know the sand filter itself is good. Any recommendations?