Hi pool people, I'm very new to this. first in ground pool. I built it myself. I filled it up Friday and could not get skimmer to draw water to pump. I was kind of panicked because I was worried about scale. I was finally able to switch 3w valve to spa, prime system then switch 3w valve to pool but only on pool vacuum. It worked fine but when I tried to switch 2w valve from vac to skimmer it lost prime and pump went into a alert mode. The only thing I can think of is pool equipment is elevated about 4/5 feet above water line and skimmer water is simply running back into pool? Any help for the green horn.