How Do You Lower CYA?

[Watermom]

Fill with fresh water on top of the plastic sheet and pump out the old water from the bottom of the pool.

[let_her_flicker]

Another option is to run a high cya pool. You do not have to drain. Just make sure you have Ben's kit and keep the cl at the appropriate level. It should not be an issue. In fact, it may be easier as the cl will be used up at a slower rate because of the high CYA. Check your cya every two weeks and adjust accordingly.

If you are chlorinating with liquid bleach, you cya will go down. If you are using stablized tablets, it will increase. Just because you cya is high doesn't mean drastic measures. Let it go down naturally and you don't have to waste water.

Back on the old forum, this was discussed and sometimes advocated as a way to operate your pool. To do this you will need Ben's kit. I hope this helps.

[cheshamjim]

let_her_flicker, I like your suggestion. You say that as long as I don't use the stabilized tablets, the CYA will go down naturally. As of two weeks ago, the only sanitizer I have used is bleach (Chlorox from a Sam's Club).

I think that the fact I have used the tablets and powdered "shock" since my pool was first opened 4 seasons ago has caused my CYA problem.

As long as I know the CYA will go down on its own without these "stabilized" products I can wait. Patience, after all, is a virtue when trying get pool water right.

Thanks for your help.

-Jim

[waterbear]

It can take a very long time for the CYA to go down on it's own, expecially if you have a cartridge filter. CYA will only go down by dilution under normal circumstances. This means refilling from splashout, backwashing a filter, or draining and refilling. Evaporation will merely concentrate it and it will dilute to where it was before when the evaporated water is replaced. Using bleach or any other non stabilized chlorine will not make it go down. However, using trichlor or dichlor will make it rise since with every use of these products you are adding more CYA!

BTW, most powdered shock is Cal Hypo (calcium hypochlorite) and is non stabilized chlorine. Dichlor is ususally only recommended for shocking spas which get drained and refilled every 3 months. It is ususally used in poos for normal sanitation.

[gordyjamz]

Last year I was running with cya of 60-70, but when opening this year I noticed it was down to 30. This was before I refilled back to normal level, at which point it was down to under 20. I had to actually raise it. I think it goes away when the water sits over the winter. So it may be less hassle to just run with higher cl level this year and see where you stand next spring and adjust accordingly then.

[crackerjack]

In The Swim has cyanuric acid remover that is capable of removing 30-50 ppm of cyanuric acid in 10,000 gallons of water.
At $50 a gallon, not sure if it would be worth it though.

[Watermom]

This has been discussed on the forum before and it is not recommended that this product be used.

[waterbear]

In The Swim has cyanuric acid remover that is capable of removing 30-50 ppm of cyanuric acid in 10,000 gallons of water.
At $50 a gallon, not sure if it would be worth it though.

It removes the cya by causing a precipitaton reaction that turns the water very milky. It is melamine, exaxtly the same as the reagent used to test for CYA in our test kits. You know what that tester tube looks like with high CYA levels...imagine your pool looking like that for a week! Also, from what feedback I have heard about CYA reducers/removers...they lower the CYA more in the range of 20 ppm per 10000 gal. Do the math. A water change is cheaper (and will probably take less time!)