Chlorine and calcium low

[aylad]

It doesn't surprise me that your CYA is over 100--the trichlor pucks in the chlorinator are not only raising your CYA with each puck that you add, but also driving your pH downward. I strongly recommend that you stop using the pucks except in emergencies (vacations, etc) and switch to liquid chlorine, or bleach.

Also, with a CYA that high and keeping the chlorine at 4-5, you are walking a very fine line between a clear pool and algae problems. With a CYa at 100 or above, you should be keeping your Cl at 8-15 ppm at all times.

If you stop using the trichlor and aerate your water, the pH will probably rise on its own. If you plan to continue using the trichlor, I'd start with about 1/2 box of Borax and aim for somewhere in the 7.5-7.6 area for pH. It's always better to add a little at a time and "sneak up" on your target number, than to overshoot it and have to correct. Same goes for baking soda to raise the alk--it only needs to come up a little bit, so I'd start with a box and go from there.

Janet

[mrszaff]

so I should shut off the chlorinator, and run the filter(is that what you mean by aerate) and add liquid chlorine? Is that correct?

[aylad]

If it were my pool, I would shut off the chlorinator, switch to bleach or liquid chlorine (same thing, bleach is 6% sodium hypochlorite, liquid chlorine is 10-12%), and aerate the water by either tossing in a group of rowdy kids, turning your return eyes upward so they ripple the water surface, and/or adding a fountain. This will stop the CYA rise, stop the pH plunge, and raise your pH to a little higher level.

If you continue to use the chlorinator, it won't be long before you have CYA levels so high that you can't maintain high enough chlorine levels to keep it clear. I'd hate to see you fighting algae all summer when it can be prevented!!



Janet

[mrszaff]

ok thanks. by the way I have been adding bleach all summer but my chlorine kept going to zero in 24 hours until this week, then I turned on the clorinator because it finally stuck. It only has 2 tabs in it that' s why I was doubting my numbers. I just threw in a gallon of liquid shock and shut off the chlorinator, the filter is on.

thanks again

[aylad]

This is a long thread, and for some reason I'm having trouble locating the volume of your pool. Since you "threw in a gallon of liquid shock", did you test for chlorine to see how high your chlorine is right now? What type of "liquid shock" did you use? You really need to get the chlorine up to at least 8 ppm.......

Janet

[mrszaff]

sodium hypochlorite,12.5%
21000 gallons in ground vinyl
I will test it again in the am and add more if needed.
keep you posted
thanks again

[aylad]

In 21K gallons, 1 gallon of 12.5% should have raised your FC by 6 ppm. I would definitely test again in the morning and add more to get back up to at least 8--and I would probably shoot for 10, just to be safe.

Janet