CYA above 140

[jblizzle]

In that case, 50ppm CYA may not be high enough to have the FC last a week.

What does the water look like? If it is already green, then clearing it at the high CYA levels is more tricky. There are some pretty big differences between owner maintained and serviced pools with the way things are done.

For example, an owner doing the shock process keeps the FC at shock level hourly and in doing so never raises the FC high enough to cause any damage. A service will come out and drop a nuclear amount of chlorine in the pool all at once which "might" be enough to kill everything at once, but it also may be causing damage to the pool and equipment.

Just want you to realize that the methods taught here may not be directly applicable to your business.

 

[UnderWaterVanya]

I just took over two weeks ago for monthly service. I show up once a week.

So having a high CYA level won't harm the pool in any way? and since I show up once a week I should leave it at that level?

It will make the level of sanitizer needed to combat algae higher than it would be otherwise. If you plan to use pucks to feed the pool you may want to get it down to a lower level and then let the pucks bring it back up over time - but eventually you'd have to drain again.

If you are only there 1/week - your options are limited.

 

[Keepinitclean]

The water looks great and the chlorine level is good. He had Algae when I took it over but not much. PH is 7.5 and Alk is 90.

What is this talk about lock up I read about? Does the chlorine lock up on high CYA levels?

So with higher CYA levels the more chlorine you will need but the FC will stay in the pool longer is that right?

 

[jblizzle]

"Lock UP" / "chlorine lock" seem to be terms people use that do not understand the chemistry and the CYA/FC relationship.

Basically as the CYA level goes up, the required FC level to keep the pool clean also goes up. Pools stores that sell pucks do not understand this, and when a FC of 5ppm is not working ... must be "chlorine lock"

Roughly: A given CYA level results in some % of FC loss to the sun each day. As the CYA level goes up, the % lost goes down.

You can likely find more info if you want it in The Deep End from chem geek.

 

[Keepinitclean]

You guys are awesome!! thanks allot for all your help...