I am glad I found this place. I have a relatively new pool (about 1.5 years old). Everything was great until about 3 months ago. It started with a very high chlorine level (both total and FC). I have been using Acucheck strips. Eventually the chlorine came down. Then a little while after I was out of town and the kids were using the pool a lot. Wife didn't know about the chlorine tablets in the Rainbow 300 and I didn't check so there was no chlorine going in the pool. It turned green by the time I got home. Now I started shocking with the powdered 1lb bags from Leslie's Pool. I could get the pool to clear up but could not get the chlorine levels to come up. I must have put 15 bags of the shock in by now and still the levels never come up. I took the water to Leslie's and they say everything looks fine. On my test strips everything PH, CYA all look good just the chlorine wont register. I told the store so they ran the more complete tests and said TDS was high (2000) and Phosphate was high (over 1000). They recommended drain and refill. I hesitated called a friend that is in pool biz he said don't drain control the phosphate. He put some phosphate remover in. I went to store and got a big jug of PhosFree. Put half in per instructions. Waited about a week then tested Phosphate still off the chart. Pu the other half of the jug in. A week later I took water to a different store NPS pool supply. Phosphate still off the chart. TDS is now over 3000. Still no chlorine. So I was considering doing the drain. I got scared by all the hydrostatic lifting issues and I also am on septic system so there is an issue of where I dump these 12,000 gallons. This is when I found your site and if I read the Pool School correctly I shouldnt pay attention to Phosphate or TDS really. Ok Im on board. I went out and got the test kit you recomended from Leslies (FAS-DPD service kit). Thats some chemistry set. I also got several jugs of liquid chlorine (planning to turn off the rainbow 300 and do this myself now BBB). First test I did was for CYA to determine the shock load. I filled up the little bottle to 7ml. Then added the CYA chemical to the 14ml line. Then swirled for 30 seconds. Then put the solution into the little vial with the black dot on the bottom a few drops at a time until I couldnt see the black dot anymore. I think I did this correct.
Holy smokes the CYA test does not even make it up to the 100 line! It looks like I might be 150-200. I guess I do the test again with half tap water and multiply by 2 to find out exactly.
Now, can this be right? All the time I have been testing with the ACCUCHECK 7 test strips it always says CYA is within the good range. I assume this is far less than 100. None of the pool stores have ever said that CYA is high? How can I be sure I am doing the test right? I really want to start the Shock Process but dont feel confident in the first test I did. BTW the Leslies test kit looks like there is only enough CYA chemical for about 3 tests so I dont want to just keep doing them. Could my CYA have elevated that much this quickly? The pool is getting greenish so I dumped a bottle of the liquid chlorine (10% pool chlorine) in this morning but I want to start the shock correctly.
Any advice on the CYA test and issue?
I will do full tests this evening and post later.