Quote Originally Posted by coryinsocal

to top it off, i forgot to switch my valve to "closed" before i vented the filter to have a look, after that, the remaining 80%of the de lot burped up out of my skimmer! lucky me, i bet that'll never happen again. everything seems to be going in the right direction, i just have about 3.5 lbs of de in my pool...
come to think of it, what usually stops the filter water from flowing back to the skimmer when you want to drain the filter? is this supposed to be built in functionality of the valve or filter? or would it just be the pump impellor? normally, i hear you don't need a check valve here (i've never had one before...)