Fw: [andorprojex] Digest Number 3081

Just a quick note about using fish tanks as thermal mass for a greenhouse:
1. There are very few food fish that can thrive in warm water (above 20C) - low oxygen solubility
2. Even fewer that will grow well with fluctuating water temps
3. Thermal mass is usually designed for high heat (sensible heat = temperature change) flux which contradicts both 1 and 2 above.

As for which species, if tilapia are allowed in your area ( very invasive species) they are an excellent start. Tolerate extremes of temperature, low oxygen, high nitrogen, etc. Almost impossible to kill. Hence why they are so invasive. They will survive in a mud puddle. Very easy while figuring out your system. They will eat anything from algae to pig poo. Thai farmers raise pigs over the ponds for this reason. Just don't let them get out.

There is a very good text book on Recirculating Aquaculture Systems (RAS) that should answer all your questions. I can dig it out if you want the author, but just search RAS and/or Amazon and see what you find.

Hope that helps some.