CYA too high, how critical is it to correct?

[jacksonlui]

hi,
This is my first post after lurking for a long time. My CYA have always been very high, about 150?, probably due to reliance on trichlor tabs.

I've since started using bleach and I also use my SWG at maximum, doesn't seem to produce enough during the summer heat (90-100).

Everyone here advocates a lower CYA and I'm tempted to drain my pool and start over and at the same time scrub my black algae with chlorine.

Does this even make sense or should I just live with a high CYA. My water is crystal clear, we use the pool very little.

thanks in advance for your advice.
J

[duraleigh]

Well, CYA of 150 is awfully high. I would try to bring it down into the range your SWG suggests.

Nevertheless, If your SWG is sized properly for the pool, you shouldn't have to run it at 100%. I'd get manufacturer's input.

I also am not positive that scrubbing the black algae when the pool is drained/lowered is a cure but it makes sense......at the least, probably quite helpful. Sounds like you could kill two birds with one stone.

[PatL34]

Your SWC seems to be working overtime, and your CYA is holding on to the Cl produced like grim death!

Try bringing the CYA down to the SWC manufacturer's specs, and you should get a better perspective of what the SWC and the CYA can do. You will then be able to lower your SWC output setting, and increase the cell life. If it means draining water, then I would do so. 150 ppm seems way too high for a SWC to handle, even at 100%.

Hope this helps.

Pat

[jacksonlui]

thanks for your reply.
I read somewhere that it's not a good idea to drain an inground pool because you don't want it to cave in and the pool is 30k gallons so it's going to cost a bit of money to fill it again.
Here are my specs. Any additional advice would be appreciated. thanks so much.

- Location: inland southern California (long hot/dry summers)
- 29k gallons
- Aquarite SWG (older model) using T-Cell15
- CL = 5ppm
- PH= 7.5 (tap water = 7.5)
- ALK = 150 (70)
- CYA =~150
- SALT = 3000
- Filter = Sta-Rite System3 Modular Media Filter
- load = 2 people once a week at 3hr intervals max

thanks
Jackson

[Sherra]

You do not have to drain it all at once. Do a 50% drain & refill...that should bring your CYA down to about 70-80. Then another 50% drain & refill would bring it down to about 40 or so.