Backyard Aquaponics
A place to discuss aquaponics

I've seen a lot of info about creating a heat sink buy digging a hole, burying some piping and covering with gravel. Force hot air into the hole to heat the gravel. Wondered if anyone has used jugs filled with water in conjunction with the buried gravel. Also thought of adding a pop can hot air collector in the mix to force hotter air into the system. Any thoughts?

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What are you trying to achieve..

It sounds like you are attempting to store heat..

The MOST efficient heat storage method is to use something that has a phase-change..

To store COLD you can first freeze water, and better - salt-water..

In order to store heat you could melt WAX... eg.. you could melt COCONUT oil and then remove that heat later when needed... this will happen at more like 24C (75F)

You can obviously use bees-wax and I think that melts at more like 65c / 150F.... so you can see that you need a higher temperature to begin with..

So - again - What are you actually trying to achieve
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