Aquaponics - Ultra low power system idea

In a normal aquaponics system, you pump water up to a grow bed, and gravity brings it back to the fish tank, Sometimes you have a sump or some other stuff in the path, but generally that's how it works.


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Pumps use a lot of power to overcome gravity.

Aquaponics can work well with the grow bed constantly flooded.

Saving electricity is environmentally always a good thing.

A power head or wave pump uses a little energy to move a lot of water, but cant lift water very well.

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Those are four important points.

A few days ago I ran the question of an ultra low energy aquaponics system through what I like to call the invention engine, and the idea seemed to be to not lift the water as high. Each time I ran it through, the water level got lower until it was zero. Some recent experiments show that for many species at least, a constant flood grow bed is a viable way of growing things aquaponically. After all, people have been growing things in deep water raft culture, where you basically fill a swimming pool with fish and float rafts that hold things like lettuce, where they happily grow until harvest time.

Just as worms have no trouble living in flood as long as the water's oxygen levels are high, a stack of plants feel the same way.

so...

If I place a fish tank next to a grow bed, fill them so they are at exactly the same level, connect them so that water enters and leaves each container from different places, and then stick a power head in the connecting pipes, we should see an effective system running on less than a half the power use of a more conventional system.

The only issue might be the restricted flow through all the media. Power heads don't create much pressure, which is why they cant move water uphill very well. But I see my water flowing very freely through my media when the siphon triggers, so I think I'm going to try it. If it works it should also be economically viable to run it from solar.

I'd really like to see more solar designs in shops.

If it doesn't work I still have a 3600LPH hour pump I can run the system with, so there is no down side for me.

The constant flood aspect isn't on trial here. We know that works. At least we know it works for many plant species. It's the power head which is the novel aspect, and the thing I will be interested in testing. It's even possible I may be able to run the system with something called an airlift using nothing but bubbles, but that's something for another post, and is only really viable if the air pump can do the job for less than the 4-6 watts I'm hoping a power head can do it for.



120 Things in 20 years, Aquaponics - Ultra low power system idea.

8 comments:

  1. So this might not be "Ultra" low power, but a positive displacement pump can lift water a great height, though often at lower than normal flow rates.

    I've seen a person post on an aquaponic forum about using a refrigerant circulation pump.
    Here's an example:
    http://www.shurflo.com/marine-products/marine-pumps/general-purpose-pumps/shurflo-specialty-pumps/default.html

    12v at a maximum of 1.5amps is not amazing, but 18 watts is pretty easy to make with PV solar.

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  2. I think the flow rate is a little low for what I have in mind.

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  3. what is a powerhead? I would like to learn more about this idea, as I have to work with solar power at my location, and it has prevented me from building an aquaponics system to date.

    I had a similar idea, but using an airlift to move the water (aeration+water moving). I think I can do about 1500 lph on about 15 watts. The key here would be to figure out how many liters per watt required. I have seen airlifts do 200 liters per watt (at low head), which is extremely efficient.

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  4. A powerhead is also known as a wave pump and is used in aquariums for water circulation. It's more like an outboard boat motor than a pump and isn't normally used to move or lift water like a pump, but rather stir a body of water, or when pulsed on and off, it can be used to create a wave, echoing backwards and forwards along the length of a pond or aquarium.

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  5. yes, I started researching as soon as I asked that question, and I have since read your long thread at BYAP, which is quite a wonderful thread!

    Anyway, I am really interested in this concept, mainly because I live in Northern Mexico, and we don't have a grid, and I would like to raise some fish.

    Airlifts could do it, though I don't know how much power would be required, maybe 5-10 watts. the power head sounds like a really good thing.

    I would be willing to test this out, if you gave me a bit of advice along the way!

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  6. Thanks. You read all of it!?

    I'd be more than happy to help out in any way I can, but I dont run any air, so dont really know what I'm talking about. But I guess it's only air, and not rocket science~.


    * to everyone else, BYAP is a forum for people interested in aquaponics and is short for backyardaquaponics.com

    ~ :)

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  7. and BullwinkleII's thread is the most entertaining and thought provoking thread on BYAP!

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  8. ok, I started a thread on BYAP to discuss a prototype of this concept: http://www.backyardaquaponics.com/forum/viewtopic.php?f=1&t=11704

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