Shallow Chilled Tank

For Christmas I got an Iceprobe Chiller. My goal is to breed some fish indoors while I wait for my pond to be ready, but the Iceprobe is not very efficient. So, my plan is to make a shallow tank, with a minimal amount of water, and chill it. To make up for how unreliable such a small volume of water is, I'm going to use a very strong filter, possibly a fluidized bed, to make sure everything works out. At most I'd want maybe 3-4 gallons of water. Any ideas on dimesions that would be good? Also, to assist the Iceprobe I'd have fans blowing both on the water, but also on the pipes. I'm aiming to have it be almost a little, shallow stream. Here's a very rough illustration of what I'm thinking of:
 Chilled Tank.png   120.06KB   9 downloads

Let me know what you think!

For better input, we'd need some more information. What species do you wish to breed. is this just a holding tank for cycling the fish or the spawning tank?

I'm planning on breeding fish like Darters, Dace, and Shiners. And I was thinking taking fish from a community tank, putting them in here to adjust their temperature, then spawning them in a 10 gallon before putting them back in their community tank. So fish woud be in here a few weeks at a time, and likely only a few pairs at a time.

Won't fans blowing on the pipes be adding heat?

The efficiency problem is best solved by working to minimize heat transfer, not by minimizing volume. A small volume of water will heat up faster as well as cool down faster, which means your chiller will need to run more often, with the attendant risks of motor failure. You should get a deep tank and work on insulating the sides. With a 15-20 gallon tank the weight should be low enough that you can use styrofoam on the bottom as well as 3 sides. If you don't need plants, you can use a pretty minimal light. Use a sponge filter rather than a centrifugal pump that will add heat directly. That chiller is plenty big enough to handle a tank of that size.

Why not test the system using a plastic cooler to see how well the chiller works when it holds a useful amount of water, say ten gallons, in the room and at the room temps that it will be used. If the goal is just to chill the fish and have a light cycle for a few weeks, perhaps a cooler with the lid off would keep the temps more stable and accomplish your goals better than a glass tank with just a bit of water. A few rocks and a sponge filter and maybe a clear lid and the fish should be happy and it would like pond life and since not much is going on you will not miss much action. You could also test it with a glass tank. My experience has been insulating a tank on the bottom and three sides of a tropical tank and I found it useful at holding in some heat but not has much has I hoped.

Why not test the system using a plastic cooler to see how well the chiller works when it holds a useful amount of water, say ten gallons, in the room and at the room temps that it will be used. If the goal is just to chill the fish and have a light cycle for a few weeks, perhaps a cooler with the lid off would keep the temps more stable and accomplish your goals better than a glass tank with just a bit of water. A few rocks and a sponge filter and maybe a clear lid and the fish should be happy and it would like pond life and since not much is going on you will not miss much action. You could also test it with a glass tank. My experience has been insulating a tank on the bottom and three sides of a tropical tank and I found it useful at holding in some heat but not has much has I hoped.

Won't fans blowing on the pipes be adding heat?

The efficiency problem is best solved by working to minimize heat transfer, not by minimizing volume. A small volume of water will heat up faster as well as cool down faster, which means your chiller will need to run more often, with the attendant risks of motor failure. You should get a deep tank and work on insulating the sides. With a 15-20 gallon tank the weight should be low enough that you can use styrofoam on the bottom as well as 3 sides. If you don't need plants, you can use a pretty minimal light. Use a sponge filter rather than a centrifugal pump that will add heat directly. That chiller is plenty big enough to handle a tank of that size.

I agree. We have several large volume saltwater tanks that we keep at 56 degrees. Several of these tanks are on the same filtration system. Our controller is set to have a 2 degree difference so that it doesn't switch on and off too much. The key to get our chillers effectively keeping the tanks cool is definitely insulation and air flow. We use foam around all but the display side of our tanks and we insulate all of our pvc plumbing in foam as well. Another big key is air flow and room temperature. The chiller should not be placed in any kind of cabinet unless there is sufficent venting, and the overall room temperature will play a role as well. Our aquarium lab is nice and chilly, and this keeps the temperature much more constant.