Finish Thompson DB3P-M612 Centrifugal Magnetic Drive Pump, Polypropylene, 1/8 HP, 115V, 1 Phase, 20.4 Max Feet of Head, 15.1 gpm

This pump works well once all nuisance details are met:It replaced a direct drive, cast-iron 1/3 hp pump with 1" intake port reduced to 1/2" size, and a1/2" output port. That pump required frequent replacement because of rust corrosion so I was thrilled with the thought of eliminating corrosion with the Finish Thompson pump and at a cost less than the cast-iron pump.With 35 years experience of using a 1/2" line from the feed tank to the cast-iron pump's 1" bushing-reduced intake port I first tried that same setup which failed miserably to reliably empty the re-filled/partially re-filled tank anytime after the tank had fully emptied and allowed air into the pump.Unfortunately my tank has a 3/4" output port which can't be changed....... and the instructions that come with the pump (which you only get after buying the pump) state that the feed line to the intake port of the pump must be a continuous 1" line from source.I couldn't change the tank's output port so I used 3/4" line from tank to pump intake, and relocated the pump from below the tank to slightly above the bottom of the tank. That assured that I could never run the tank dry and ingest air into the pump, which has trouble being cleared if the input line to the pump is less than 1"To get the best result from this pump keep the following two thoughts in mind:1. It requires (or does best with) a continuous 1 inch feed line from fluid source. Anything less and it potentially starves for volume and is unable to clear an occasional air bubble if it ingests air from the source tank feeding it.2. It must be located at or slightly above the bottom level of the feed tank it draws from. Doing so prevents air from entering the pump and thereby creating a partial loss of prime resulting in a reduced flow....or no flow at all even when the tank fills up again.