1st test of the season

[maxsrents]

Our pool was opened on Wed. and these are the first test results:

FC 3.0
TAC 3.0
TH 100
CYA 150
TA 120
pH 7.8

We were told to add 36 lbs of calcium hardness. Do you agree? And is there anything else that needs to be done?

Thanks for your help.

 

[JasonLion]

Yes, 35 lbs of calcium increaser is a good idea. That should get your calcium harness up to 200 or just a little bit more.

CYA at 150 is very high. If that number is right you need to keep FC between 12 and 18. I strongly recommend that you get your CYA below 100. The only practical way to reduce CYA is to replace water. If you are replacing water you should do so before adding the calcium.

 

[Guest]

I concur with Jason.

 

[maxsrents]

Thanks so much for the info. How much water needs to be replaced, in order to affect the CYA? And if we replace water and add the calcium increaser when can the kids swim? They are hocking us to go in. Would it be so bad if they jumped in today-with the way the pool chemistry is now??

 

[JasonLion]

You should replace just over 1/3 of the water, enough to get the CYA level under 100. Since the tests that are able to measure CYA levels over 100 aren't all that accurate it might be best to do a little extra just to be sure. You can do the water replacement various ways, partial drain and refill or continuously adding and removing water at the same time. Unless you have a very high water table it is generally safe to lower the water level about 18" below the skimmer.

If the water is clear and you bring the FC level up to 12 or higher the pool will be fine to swim in for now. Add five gallons of 6% bleach and let it circulate for an hour and that should take care of things for today. As long as the water remains clear and you keep the FC at 12 or higher at all times (aim for perhaps 15, so that it doesn't go under 12) you can limp along with high CYA for a little while.

If the water isn't clear don't even think about swimming.

 

[maxsrents]

The water is beautifully clear, which is why the kids are busting to go in. We just added about 1/3 of water on Wed. prior to removal of the cover. The pool co. then added chemicals-can the high CYA reading be related to the algaecide and shock they added?

 

[JasonLion]

There are a variety of "shock" products, some have CYA in them and some don't.

 

[duraleigh]

Go swimming and enjoy.

At some point, it would be a great idea to get your CYA down into the 40-60 range. The only way to do that is to drain and refill. If it's 150 now, that'll require almost two 40% refills. You can do them weeks apart and at your convenience. If you choose not to, virtually EVERYTHING in your pool water maintenance becomes more difficult.