I was using a Taylor kit for chlorine and pH, and then a different kit for the Alk and hardness (blue box kit, don't know the brand).

I have a Tagelus 60D sand filter, rated for about 60 gpm, my pump does somewhere around 30 gpm. I installed the pump and filter myself.

Quote Originally Posted by PoolDoc View Post
Tell us how you are testing, and what the numbers are. (If you've hung around here & TFP, you know we're probably going to tell you to get another kit, unless you have one of my old kits, a Taylor K2006 or the TFP kit!)

Tell me what make / model of filter you have.

I'm just guessing, without that info, but my guess is you've installed a filter that's too small, and have blown most of the sand out, when backwashing.

(BTW, Lisa, sand normally is NOT present in backwash. When it is, the sand is not properly graded OR the filter is too small. Of course, that describes more than 3/4 of pools with sand filters, so I guess it is "normal" in the statistical sense. But it's not 'right'!)

Ben