Here are my numbers; am I good to close?

[SandyDittmer]

Hello,

I have an AG, vinyl lined pool with deep end, 13,500 gallons, use bleach for sanitizer, borax and baking soda when necessary.

I am using test kit PS233. Here are my numbers. Am I good to close, or do I need to raise the pH and TA a bit? I showed the TA as a range since at 80 the sample was barely pink, and at 90 it was a vivid pink. Water is crystal clear, and no signs of algae whatsoever.

pH 7.2
TA 80-90
Fr Ch 6.5
Cmb Ch 0
CYA 38

I read somewhere that a sand filter will filter out polyquat. Is this true??? I battled with mustard algae this summer, and I got advice here to maintain a high chlorine level for a certain timeframe, and I did finally get rid of the beast. I then added half a bottle of polyquat to help prevent more from coming once I got it cleared up. But, I WAS running my filter. If a sand filter takes the polyquat out, what would be the sense of purchasing polyquat?

I use a winter cover (solid) because of leaves falling. I had always had my water at shock level when I closed the pool in the past, but now I read that damages the cover so I should just close the pool with my chlorine at the high end of my range. Is this also correct?

Thanks for any advice.

Sandy Dittmer

[Poconos]

Sandy,
Can't comment on the polyquat as I don't use it but CarlD will probably chime in. Only thing I would do is raise the pH to the 7.6-7.8 range to allow for dropping due to dilution and maybe acid rain over the Winter. You don't want to run the risk of the water going acidic with a vinyl liner and 7.2 is a little too close to neutral for comfort. By the time I winterize the equipment the water is too cold for even the polar bear club members. I don't cover but still only run the FC up to 3 to 5 or so. Nothing critical.
Al

[aylad]

I don't use the polyquat either, but somewhere along the line Ben had posted some closing guidelines, and in them he indicated that the filter would take out the polyquat, which is why he recommended putting the filter on recirculate for a couple of days after adding it.

Janet