Nice article Elaine.
It's a little short on detail. I'm thinking they compost on top of their water pipes which keeps the temp up when it's really cold over there. They pre-filter the water before it goes to their grow beds with water cress. That's kinda interesting and avoids the need for a radial flow filters that a lot of folks use (not me, I keep it really simple). The pre-filter business means they don't have to clean the grow beds out very often.
I would have hated to have had to work out the numbers on a system this big. Fish to grow bed size to water volume etc.
Having said all that, why can't we set up these kinds of things in poor countries? Not this exact model, but low power versions (yes, they exist using "ram pumps").
It is indeed short on detail!
Do you mean a hydraulic ram? I recall seeing my first one in a paddock outside Tumut. My Dad an engineer with lots of 'unhockable knowledge' knew what it was and explained its workings. Just read an article on them, they've been around in current form for around 200 years and before that there were designs and versions of them working. Snag as I see it is the 'waste water' which needs to be re-circulated or re-directed.
Yes indeedy - that is what I mean. I'm sure a little concrete could be used to recycle the waste water back on itself.
Hydraulic ram pumps work on the principle that there is a continuous/permanent source of water, usually a river or a large dam which can be re-filled before the source runs out. The method of refill can be natural river flow, or water run-off from somewhere above the source, or it can be re-filled by a person-made process (that is a pump other than the ram being used ... the 1st law of thermodynamics limit the ram pump from efficiently feeding back on itself). Person power may be another possible option. These pumps usually work on the principle that nature provides the permanent source due to inefficiency in alternate water return principles.
3rd world/ developing countries (and hopefully, one day my back yard) would benefit from a system like iavs due to it's simplicity and low power requirements ... 5th point in the iavs link ...
It's the original flood and drain type of Aquaponics (before the AP terminology came into play) developed by Dr. Mark R. McMurtry. The largest differences to present systems are ... the use of specific sand types, far less energy required to run and no pre-filtration. It seems to be just getting re-visited/revived presently, with a large project in India underway.