Walmart will have the Rule bilge pumps that have styrofoam around them so they will float and a piece of PVC pointing up. It has a sort of cap on top that makes the water shoot back down and disperses it. Look in the fishing section. If not, just get the bilge pump, about 400-500 gal/hr. and add your own pipe with 2 90 degrees to point it back down. Put a screen over it like sink faucet aerator.
A trickle charger for battery will not hurt it. Get one that charges at 2 amps more than the pump draws. That is a good idea. I suggest letting it run on battery for a few hrs. weekly to keep the battery in good condition.
While at Walmart, go to plumbing and get a bag of Septic microbes. It comes in a red bag and is 5 bags inside that are to be flushed down the toilet in septic systems. Put part of a bag in the tank. The microbes will help keep the water in good condition.
