Backyard Aquaponics
A place to discuss aquaponics

Something extra to add to your bag of tricks

If you have a fish tank that's in danger of getting to hot even though it's buried, wetting the soil around the tank should help. See the section on Heat Capacity - http://builditsolar.com/Projects/Cooling/EarthTemperatures.htm

Soaker hose might work well for this sort of thing.

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I would wonder if it is not just better to wrap the whole thing in GOOD Insulation, from the outset..

I luckily found a source of used double-foiled foam PE to wrap my tanks, and it does look pretty good..



my logic - better to be 100% insulated than say 30% BURIED..
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Wetting the soil can certainly help initially if the soil is cool, but if the sun is shining on that soil, it will be a much better conductor of heat into your FT.
I'd suggest only wetting the soil around the FT if you can shade the ground when the sun is out.

Isn't the heat loss through the grow beds the defining factor?

Heat gain into GBs in the sun is definitely a greater contributor, but if you have dealt with that as much as you can and are looking for more protection from heat gain, then doing something about other sources of heat is important.

Yep, what Guna says, heat travels from hot to cold so anywhere you can minimise this transfer will assist.
I've got a couple of cooling ideas in the planning stage at the moment including scottys original post but I'm planning to cool the sump instead.