18'x34'x52" buried inground with a Hayward ProMatrix 1 hp filter. We recently had the pool installed by a professional. He hard plumbed the pump & filter and when he did that he placed a check valve on the pump to keep it primed. At the time we didn't know you couldn't install an AG pump above water level. We moved the pump/filter, which is now about 20' from the pool. I have not been successful in getting the pump primed. I had a middle of the night revelation and wonder if this will work and after I've done some web searching the only thing I have found so far is check valve installed vertically. Our check valve is installed horizontially right at the pump. To me it makes more sense to install the check valve at or closer to the skimmer so I don't lose the water that is in the line. We'd like to give this one more shot before we suck it up and pay ton of money for a new inground filter.