SWCG + variable pump

[swimdaddy]

Are you sure you are not fighting algae? What level of chlorine are you trying to maintain? Does it drop quickly between cycles? If it does, either your are fighting something or your CYA is low. If it doesn't, its probably something mechanical, like your cell (they do go bad) or what FBU mentioned already. Running the SWCG at 100% is going to kill it right fast, so I would be supplementing with bleach. Posting a full set of numbers might help the mods answer your questions.

[JimK]

As long as is enough water flow for the SWCG to come on, you shouldn't have to crank it up like that. I take it you're not getting any no flow warnings from the SWCG?

Like others mentioned, my guess is you're fighting something or the cell is getting ready to die, or perhaps the cell needs to be cleaned.