You can just run a drip into the top of tank. You get a drip emitter from lowes or homedepot. They come in different gph flows. So that would get hooked into your water line in the house somewhere. Most people use a regulator before the emitter to bring the psi down a bit. Easiest way is to have your sump drilled to the water level you desire and run a bulkhead and drain out somewhere. I set up a auto changer on mine using a Toro lawn sprinkler timer and valve It clicks on everyday and dumps 80g of fresh water into the tank. I didn't have my sump drilled so I have a mag drive 9.5 pump hooked to a float valve so when my sump fills up it pumps water out into my lawn. If I had the chance to do it again I would have had sump drilled.
