Cooling Options for fish tanks

[KentUB]

I have been attempting to find somewhat reasonable cooling options to beat the summer heat so I can keep trout or other cool water fish. So I have been researching with Google quite a bit and found an interesting item.

Evaporative cooling will cool both air and water to the wet buld temperature of the ambiant air. The University of Florida has a research paper on Evaprotive Cooling for Aquaculture, which I am attaching here.

The critical factor is Design Wet Bulb Temperature. Some of these can be found online for certain cities. If you can not find your specific areas can not be found you should be able to get this data from any HVAC installer, as they use these figures in their design and energy audit programs to properly size HVAC installations. These figures are based on historical temp and humidity figures.

From the figures I have found so far, I am worried I will also need some form of mechanical cooling as I would be running very close to the upper tolerance on those 1% days. So the search continues.

[GoneFish'n]

With Utah's low humidity, yearly average about 35 percent and summer time average 15 to 20 percent, evaporative cooling should work well. If it works in Florida, it has to be much more efficient in Utah.

[nwestwood]

My greenhouse is one big evaporative cooler, but on those hot summer days when we get above 95-100 degrees, the greenhouse runs up to 85-90. In the summer I turn off the water heating for the fish tanks and let the temps drift down at night (68-69) and on hot days they run up to 76-78 degree's. I was able to cool them 1-2 degrees by floating frozen ice (big blocks, or frozen milk jugs). You could probably float several and reduce it further, but that was just to keep it from super heating. The lettuce bolts at those temperatures, it's best if the water is kept below 74 and 70-72 seems to be the best for a lettuce/tomatoe mix. The tomotoes love the warmer water, but the lettuce does not. The tomatoes, cucumbers and bell peppers stopped growing and fruiting below 68. Nelson and Pade found that they could control the tank temps by insulating the tanks, pipes and raft tanks. I have my tank insulated but not the rest.

[mpmace]

So are you saying that I'll need to keep my water between 74 and 68? That's going to be very difficult in Beryl where the days get up to 100 and the nights cool down to the 50's.

[KentUB]

It will depend on the fish that you use. If you need cooling you will need to find the "Design Wet buld" tempatures for your area. With the Evaporative Cooling system attached above, you can cool air and water. If you get your water temps down at night they will slowly creep up during the day, but not as fast as air temps.

[nwestwood]

If you have the inclination, you can bury a plastic pipe underground hooked to a heating/cooling exchange. a search of some of the other sites will give you more details, but basically, you , run either the tank water, or a secondary cooling system water with some sort of non-metalic heat exchanger. The ground, maintaining a more stable temperature. In the summer, the ground cools and in winter the ground heats. Likewise black plastic coils on a roof in the winter will heat the water. It was to much engineering and expense for me, but it can be made to work.

[mpmace]

Are you nuts? I'm too cheap to even buy a greenhouse do you really think I'm going to pay someone to dig a hole? I'd have my kids do it, but I can't even get them to clean their rooms!

[dufflight]

Bury the fish tank. There is also making an outer wall around a ft and fill it with sand. You keep the sand wet and it cools via evaporation. Also running a bio filter in the day and pumping through the gb's of a night.