My spa has two drains: one on the floor and one on the wall. Only the drain on the wall appears to be sucking any water. This is slightly annoying because debris settles at the bottom and stays there. If I sweep debris towards the drain on the wall, most of it gets pulled into the drain, but it can be a little like playing whack-a-mole as I watch it eventually settle at the bottom again.
Is this the correct behavior? Am I right to assume that if I covered the drain on the wall somehow, that the bottom drain should suck water? Or is this a sign that my bottom drain may be clogged?