Doesn't everyone?
I find hermits very entertaining. I once watched one climb the silicone seam in the corner of my tank, for over a half an hour. Stoopid thing would climb, making it nearly to the top, then fall off and start over again.
You would probably not be surprised to know that I enjoy the same observations. I even do little voiceovers in my head.
Finished the electronics for the ATO today at lunchtime and they're tested working. Just need to get some PVC parts to finish the bracket for the float switches and it's done.
A while back I bought a whole bunch of peristaltic pumps on eBay. They're a weird pump - 24v DC motor with a huge gear drive on it. I have plenty of 24v DC power so that part was no problem. Initially I figured I'd use one for ATO, two for dosing two-part, and two for automatic water changes. So today I put one in service for the ATO, but I'm not sure about the rest of my initial plans - I'm probably just going to use kalk in my topoff instead of two part, and these pumps might be a hair slow for an automatic water change, though I suppose that's subjective.
The ATO is actuated by two standard-issue float switches on a bracket in the sump. They are wired in series, so they are redundant - both have to be open for the circuit to turn on. One will be mounted about a quarter inch higher than the other as a failsafe.
The switches are wired to the coil side of a 24v relay. The relay is rated for 10A which should be vastly more than the pump(s) draw.
The ATO pump is located in the basement near the water change station, and there is airline hose running up through the floor to the sump. The end of the hose is above water level to prevent the potential for back siphoning, though of course the peristaltic pump prevents that on it's own.
I specifically chose a peristaltic pump because it'll have no problem with the head height, and it's a v-e-r-y slow flow rate, so if something DOES go wrong and it gets "stuck" on, it won't cause a problem for a long, long time.
So, float switch triggers when water drops, relay switches pump on, pump adds topoff water to the tank from the RO/DI reservoir. Pretty standard stuff! Once I get the kalk reactor design finished I'll put that inline with the topoff and the tank will be all set for calcium, alkalinity, and topoff.
FWIW I'm evaporating less than I'd expected. Don't have a real rate yet, but I'm guessing it's between a gallon and two gallons per day. I was expecting more like three to five, based on feedback from others with tanks this big.
I want surprises from time to time.
