Hmmm...now I'm more confused. We just had our filters cleaned about 2 mths (or less) ago, so I'd be surprised if they were already bad. It's cartridge, not DE. I don't have any idea how to take apart the filter thing; I'd have to call someone for that. Do you think it's imperative, given we just had them done?

Is it an option to shock it up to 25ppm via regular shock powder...get it stable...and then start the BBB method? I'm pretty petite and if it's likely I'll need 20 gal of bleach over the next few days, then I'm wondering if it'd be easier (for now) to just get the shock and later start BBB.

Thoughts?

Again, thanks for your help.