1/2 HP 2400gph Pump @ home depot for $89.95?

[CHOMPERS]

then explain why this pump puts out 3600+ gph?

A pumps output is not an indication of whether it is built for continuous duty. I would say the one from HD is more likely to stand the test of time rather than the one from Harbor Freight for half the price.

Sump pumps are intended for intermittent duty. That is why they have float switches. I ran a Little Giant sump pump continuously on my system. The only problem I had was excessive corrosion in the aluminum body.

 

[nbku3vm]

This looks like an evap cooler pump to me. I'm not sure, but if it is, the whole thing is not designed to be submersible. It is ment to be sat in a traugh about 3-6 inches deep and pump water on to the cooling pads when needed. This means that the top of the pump where the electrical connections are is well out of the water. Yes it gets wet, but it is more like being rained on insted of submerged. I'm not saying it can't be fully submerged, but I'm not sure how long the seals would be resistant to water penetration.