You have an interesting idea with the heated water thing, but are you totally sure that your temps are not stable? If you have even a fluorescent light above your tank and it's on for 12 or more hours a day you'd be amazed at how warm it can get inside your tank. Limiting ventilation will also help trap and hold in heat and is something you typically want to do anyway to keep fruit flies and humidity IN the cage instead of letting it all out. I have several dart frog tanks and some other species of frogs. All of my set ups have a single fixture 48 inch two bulb T8 fluorescent above a single row of three to four 10 gallon tanks [on edge]. My tanks [even in a room that gets into the low 70s or high 60s] still maintain temps in the high 70s throughout the day with a nighttime temp drop of a few degrees which is actually beneficial. If you haven't already, I'd get a temp gun and just spot check your temps throughout the day and see just what type of range you're getting. Other than that, I like the idea of the heat transfer via the water but if you've got a fairly deep substrate you're going to lose a lot of that heat. Also, you're going to have to heat your water up to somewhere in the 90s in order to not lose too much heat before it gets back into the aquarium and for it to even have an appreciable effect on heating the terrarium. That's a water temp you DON'T want your frogs coming into contact with. A better solution is probably a low wattage radiant heat panel suspended above the tank and hook up to a proportional thermostat with the probe inside the tank. Expensive and cumbersome to say the least. You can do a lot more with perhaps moving the lights closer to increase heat, limiting ventilation, or even insulating the outside of the tank.
>>I'm looking for the best way to keep a steady temperature in a dart frog vivarium. The temperature in my house tends to vary a good bit, so I'm kind of iffy on what to do.
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>>My vivarium is going to have a false bottom, with maybe an inch of water in it. This isn't enough to put a submersible heater in, and I hesitate to put a heater under a false bottom anyway, because any time it needed adjusted, the whole thing would have to be torn apart.
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>>My thought is to build something similar to an external canister filter for an aquarium, except without filtration (except some screen to keep debris out of the pump). On one end of the cage, the intake tube would suck water out of the false bottom, and pull it into a large plastic container. The container would hold a pump, and a aquarium heater. The pump would force the water back into the vivarium by powering a waterfall/river that would then overflow into the false bottom of the vivarium. The water would be warm, and thus keep the vivarium itself warm.
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>>Does this seem like it would work? Does anyone see any flaws with the idea?
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>>thanks,
>>Ronnie Nocera
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Matt Campbell
"I only went out for a walk and finally concluded to stay out till sundown, for going out, I found, was really going in." John Muir
