It's pretty much set up like a DIY surge tank...instead of the water being pumped into the rubber tank, it is gravity fed by a 1/4" line...like RO tubing, just tapped into a cold water line. In Florida ( I have a place in Dunedin...south of you, off of 19) I would probably just leave it outside.... hook up a timer to the hose faucet and have it turn on a couple of times a day. You could leave it in a sunny spot that would warm up the water and speed the process. In the interest of saving water, you could just fill and dump it once a day. Plumb the tub like a toilet tank...drill a hole in bottom, a put the flush valve inside and thread ring from outside to seal. The overflow tube serves no purpose but to stabilize the tank flap and float. Adjust the float ball to height you want...when water reaches the correct level, the flush valve will be activated and dump the water. The metal chain that is usually attached to the rod for flushing, is instead attached directly to the float. A plastic ring, height whatever you want, is siliconed around the whole float valve assembly. The water will empty to that point and leave the water still covering the rock so they don't dry out.
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