Quote Originally Posted by mas985 View Post
For the same CYA level, higher CL levels require higher % setting or longer pump run time. How else would you get the higher CL level?
Keep in mind I'm just talking about maintaining a given CL level, not increasing the level (liquid CL can be used to get to the target level).

On the surface it seems maintaining CL level just requires the SWCG to generate enough CL to replace what's lost. If true, then the SWCG% and runtime should be the same whether you're maintaining 4 ppm or 8 ppm (CYA woukd be kept at 80 ppm) assuming CL loss is the same at both CL levels. However, if CL loss is greater when trying to maintain the higher CL level with a set CYA level of 80 ppm, then the SWCG would have to run longer and/or higher %. I'm trying to figure out which of these is true.

My recent experience with the CL level dropping at an even rate each day (1.5 ppm per day) from 20 ppm to 5 ppm (CYA remained at 80 ppm) suggests that the rate of loss isn't faster at higher CL levels.

I hope I'm making sense (it makes sense in my own head....lol).