Backyard Aquaponics
A place to discuss aquaponics

What is the a maximum length for the DWC and Ebb and flow systems? I am assuming it would depend on water flow, amount of fish in the tank, and the size of the tank. Is there a formula to figure out or would it be trial and error?

Right now I am looking at approximately lengths 200 ft (61 m) for they DWC systems and 80 ft (24.3 m) for the Ebb and flow systems.

Currently I have a backyard system and I am working with multiple partners on the possibility of doing a large scale aquaponics.

Scot

Don't use "ebb & flow"... use "flood & drain"....

The question is... why do you, or would you... incorporate media beds in a "large scale" system anyway...

I was looking to do the "flood and drain" system for the larger plants like tomatoes, cucumbers, ect that would be impractical for DWC. Then I would use the DWC for the lettuce and other low center of gravity greens.

The reason why I ask this questions is because I have seen DWC systems that flow into another DWC system that flow into another DWC system and so on. At some point the nutrients in that water will be exhausted, I am trying to see if anyone has experimented with longer grow beds. So far the longest I have seen (on the internet) is about 60 feet.

It's not so much the nutrient depletion over length... but the oxygen depletion....

You should take a look at Dr Rakocys work at UVI. It is the longest standing production model that everyone seems to be forgetting about these days. Jim ran 200' runs of DWC for 20+ years. As you mentioned, length will very somewhat with the crop being grown. A second inlet point in the trough can always be used for longer runs as long as you have enough head pressure to push the water that far away. I would keep any F+D beds in the smaller side or you will need a huge sump.

Yep, just duplicate the UVI style...

And forget the media beds.. if you're doing "large scale"... or "commercial aquaponics"

The basic design that I have is similar to the set up at UVI. The main difference is I am looking at is 1 tank per 4 DWC grow bed with a total of 4 tanks and 16 grow beds. I am looking at separate systems in case of a some sort of outbreak in the fish or bacteria in the water that kills the system. Then whole operation would not be a loss.

The flood and drain system I am looking at is only about 8 - 10 inches wide.

I need to mention this will be a non-profit and currently I have a "partnership" with the WDVA (Washington Department of Veterans Affairs). This will be an alternative therapy device for PTSD with the profits from this operation funding other alternative therapy for PTSD (training service animals and working with horses). I also have interest from 2 major universities and master gardeners association of Washington. That is why I would like a flood and drain system as well.

Cool.. have a separate media flood & drain system... to the same specs as a DWC raft system...then you can compare the yields/performance...