Phosphates?

[Charlie]

Thanks for the responses. The issue with the Pool Pilot was last year. As soon as I got around the 500ppm level, the unit began generating chlorine again. It was the first question that the Pool Pilot tech asked me while we were on the phone discussing the issue.

As of 11-10-07:
FC = 1.8
CC = 0
pH = 7.6
TA = 90
CH = 500
CYA = <20
Salt = 3000
water temp: ~60°F

The water is crystal clear. If you were to throw a quarter in the water, you can tell if it's heads or tails. Looks like my CYA is too low. I believe the correct range is 60-80? If I was to use triclor tablets, that will raise the CYA correct?

[aylad]

If I was to use triclor tablets, that will raise the CYA correct?

Yes, trichlor will raise your CYA. Just keep an eye on your pH--CYA will lower it. Of course, with a SWG, if you're having to constantly add acid, that would be a good thing!

Janet

[waterbear]

I would not use trichlor to raise your CYA since it is so low right now. It will take quite a while to get enough CYA in the water by using trichlor and CYA is important to make sure the cell is operating properly and not being overstressed. I sould just go ahead and add enought to bring your level up to about 70 ppm. Perhaps this was your initial problem since the phosphates really have no bearing on chlorine production but having low CYA and a chlorine demand or having the pool exposed to sunlight WILL make it impossible to maintain a FC level in the pool. Also, inspect your cell regularly for scaling since your CH is 500 ppm. and be sure to keep close tabs on your pH and do not let it get above about 7.8 since high pH is the MOST important factor in creating scaling conditions with high calcium. Scaling will also inhibit chlorine produciton.
Finally, once you get your CYA up into the proper range maintain your FC between 3-5 ppm. You should have no problem then.

[chem geek]

To add to what waterbear said, you have a couple of easy options to add CYA quickly. One is to use Dichlor since that dissolves quickly and for every 1 ppm FC added by Dichlor, it also adds 0.9 ppm to CYA. So using Dichlor as a chlorine source will help, but it will still take a while to add 60+ ppm CYA, but is something you can do in addition to the other option below (if you want).

The fastest and least expensive option is to get pure Cyanuric Acid (CYA). This dissolves slowly, however, so you need to put it into panty hose or a sock and hang it over a return flow. That way, it will dissolve in about a day, maybe two, if you keep the pump running 24/7 until fully dissolved. I suppose you could put it into a panty hose or a sock and put that into the skimmer (being careful not to fully block the water flow) as another option. Lastly, you could add it carefully and slowly to the skimmer (with the basket removed) directly and have it get caught in the filter, but that takes longer to dissolve (about a week) as the water flow per unit area in a filter is far lower than in the skimmer itself or from a return flow.

Richard