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wilcfr
07-10-2008, 09:57 PM
We now have a salt chlorinator on our pool. To make it work properly you have to have the proper level of CA in the pool to stabilize the chlorine being generated. We can't seem to get any CA to show in our pool. We have a 38000 gallon gunnite pool and have added 17 pounds of stabilizer and it still shows 0ppm. Any suggests as how to correct this problem would be helpful.

pH 7.1
Alk 130
total Cl 1.5ppm
free Cl 0.5ppm
Hardness 600ppm

The pool is crystal clear, smells great and has no algae. The chlorinator is a Jandy set at 100% right now. It has been set at 55% and 75% with the same Cl results of .5 and 1.5. We added 8 gallons of liquid chlorine on two separate days because of heavy use with no movement in the Cl numbers. We use Hach kits for testing the Cl, Alk and hardness and a hand held pH meter for pH. We are presently testing the CA with a test strip as we await a Taylor test kit. Our local Leslie's tester show 0ppm when he test for CA also.

Thanks

CarlD
07-10-2008, 10:25 PM
CA is calcium, not stabilizer. Your calcium level is already high--too high at 600. You probably should drain off 1/3 of your water and replace, or just watch for scaling and not add anything with calcium.

What you want is CYA--Stabilizer. CYA can take from 48 hours to a week to dissolve in. If you put it in your skimmer, you cannot backwash for a week, just to be safe.

Strips are hilariously unreliable when it comes to CYA. I've been checking them against my drop test for 7 years and STILL can't figure out how to read them correctly. You need a proper drop-test kit.

You should, as everyone should, have a proper test kit that uses the FAS-DPD Chlorine test--much more accurate and thorough than strips. Such kits come with the CYA test as well. We recommend any one of 3: The Taylortechnologies.com K-2006 (or K-2006C), the Lesliespool.com FAS-DPD Chlorine Service Test kit, or the Troublefreepools.com link to the TF-100 test kit. There's another source for the Taylor K-2006 that's very reasonable--I don't remember the link, but the kit is $50.

Spending $50 to $75 on a proper test kit is the best investment you'll make in your pool.

wilcfr
07-10-2008, 11:07 PM
A little misunderstanding when I said CA I meant Cyanuric Acid not calcium though I know that Ca is the chemical symbol for calcium my mistake. We are awaiting our drop test. It was supposed to be here a couple of days ago, we are still waiting. The first 5 lbs of CYA has been in the pool for 2 weeks and the remaining 12 for 5 days. We did not back wash after the first 5 lbs. We waited for 3 days after the 12 lbs was added per the instructions on the tub. The only reason I back washed was the filter gauge was showing almost 30 psi over twice what it normally runs. Hopefully the drop test will show some CYA in the pool. I do not want to run the chlorinator at 100% forever, but I also do not want a crappy pool or to have to continue to add liquid Cl.