Understanding Cya Management.

[DaveH24]

Hi

Having run a bromine hot tub I haven't had to worry about CYA and to be honest I was considering running my outdoor pool on bromine , until I searched for and found the post from waterbear saying don't.

From what I've read on this forum so far it seams that CYA is a nightmare, as you need it to stop Chlorine loss but it reduces the effectiveness of the chlorine. The chlorine seems to be used up , so you have to add more , but unless you are adding liquid chlorine, you have to use tabs which add CYA to the pool.

What stops the CYA level from continually increasing, and how do you manage its level ?, does it get used up somehow ?

Thanks

Dave

[chem geek]

You just add chlorinating liquid or bleach (or use a peristaltic pump or The Liquidator for dosing it) or you get a saltwater chlorine generator. You can use some Trichlor now and then for convenience if you raise the FC proportionately as the CYA level rises. If you have a small pool with summer rain overflow and a sand filter you backwash and a short season, then the water dilution can be enough to let you use Trichlor pucks the entire season. If you have a low Calcium Hardness (CH) level then you can use Cal-Hypo as another alternative.

The other, more expensive, alternative is to not worry about the CYA level and use supplemental algaecides or phosphate removers to help control algae growth.