Couple of questions I can't find the answer to.

[AndyBSN]

Why do saltwater pools have to maintane a higher cya level?

Are chloraimines still possible?

If I have to SLAM my pool, or chloraimines are an issue. How high can I go with chlorine level that is safe for a vinyl liner? I've seen the shock levels for salt pools and they are HIGH. Like swimming in bleach high.

 

[mknauss]

Pool Water Chemistry -- read post #5

Sure. That is CC

SLAM level. Even then, the active chlorine is less than in a pool with 3ppm FC and 0 CYA.
Pool Water Chemistry -- read post #1

 

[jblizzle]

The higher CYA better protects the FC from the sun and allows the SWG to run less and prolong its life. You don't have to run the CYA that high if you don't want to.

The CYA also buffers the harshness of the chlorine. So there is no danger to the liner at the higher FC levels. At the shock level for any CYA, the pool is less harsh than a non stabilized indoor public pool work a FC of 2ppm.

 

[zea3]

SWGs distribute chlorine in small amounts over an extended period of time. Without higher CYA levels the chlorine would be lost to the sun before they could sanitize the pool.

Chloramines are possible whenever you introduce organic matter to the pool. Chloramines are the waste product of chlorine oxidation. They are constantly being produced and broken down, which is why CC of 0 -.5 is normal. When the chlorine is overwhelmed with more organic matter than it can oxidize, such as an algae bloom, chloramines build up in the water as there is insufficient chlorine to further break them down.

How high your chlorine levels can safely go depends on your CYA level. CYA buffers the chlorine, so that an FC of 5ppm with a CYA of 30 is actually gentler on swimmers than an FC of 1ppm with 0 CYA.

 

[AndyBSN]

Thanks all.

A quote from the post by ChemGeek

Going from 30 ppm to 90 ppm requires about triple the FC level, but the loss rate may be cut down by a factor of 7 for a net overall savings of over a factor of 2. If we can validate this, then it should be possible to run a high CYA pool with high FC levels economically, especially in deeper pools.


So I understand CYA as a buffer for chlorine and UV radiation. Why wouldn't a traditional pool run the same CYA level and a higher FC level, if there is a net savings? (I now some people do but it's not recommended) Is it because the quality of the chlorine in a SWG is better and more effective so it can run at lower FC levels than a traditional pool for the same CYA level?


Thanks for the replies and pointing me to these post.

 

[ajw22]

So I understand CYA as a buffer for chlorine and UV radiation. Why wouldn't a traditional pool run the same CYA level and a higher FC level, if there is a net savings? (I now some people do but it's not recommended) Is it because the quality of the chlorine in a SWG is better and more effective so it can run at lower FC levels than a traditional pool for the same CYA level?

A SWG pool with a properly set SWG % output running during the day maintains a consistent level of FC replacing what is burnt off by the sun. If you added liquid chlorine in small doses hourly to a traditional pool you could run it at lower FC levels.

Study this chart [FC/CYA][/FC/CYA] for the same CYA level. A non-SWG pool has a higher target range to allow for 24 hours of FC loss before you test and add FC.