Mixed Aquaponics Design
Do you combine different media, methods or even culture species in such a way that no rules or system descriptions out there really applies to you? This is the place to share, ask questions, learn and refine.
Pump in DWT - raft/sump
I've been designing a hybrid system for some time now combining media beds with DWT and nft and i am starting to see some surprising benefits. My plan is to let the f&d media beds flood into the DWT so that the rafts rise and fall with the fluctuating water levels. With the DWT having so much more volume than the media beds, the water level would not change too drastically.
I've read a lot of posts about the challenges of getting enough oxygen to plants in rafts and I'm now fairly convinced that the way to go is to install a lip along the inside length of the trough such that the rafts cannot sink down below a minimum height. This way, when the water drops because it is filling media beds the rafts will be suspended and the upper portion of the roots exposed temporarily to air. This regular action would bring oxygen directly to all of the DWT plants without the use of any air pump at all!
Additionally, this makes it possible to mount the DWT plants into something other than a styrofoam raft. Although one big bonus to the foam is that it is great at insulating the water in the trough.
I'm going to give this approach a try on my new system. It should reduce the energy needs to run the system and make it even more suitable for off-the-grid installations!
I've read a lot of posts about the challenges of getting enough oxygen to plants in rafts and I'm now fairly convinced that the way to go is to install a lip along the inside length of the trough such that the rafts cannot sink down below a minimum height. This way, when the water drops because it is filling media beds the rafts will be suspended and the upper portion of the roots exposed temporarily to air. This regular action would bring oxygen directly to all of the DWT plants without the use of any air pump at all!
Additionally, this makes it possible to mount the DWT plants into something other than a styrofoam raft. Although one big bonus to the foam is that it is great at insulating the water in the trough.
I'm going to give this approach a try on my new system. It should reduce the energy needs to run the system and make it even more suitable for off-the-grid installations!
Dan Ponton
Yup, I have seem that a lot of you-tube, but I think it's with the 2" foam rafts. I think keeping the raft a little above the water line is a good idea, but I am new at this myself.
I will use one of the two ideas myself.
Apr 17, 2012
Bart
Averan, did you ever build this system?
I'm in the process of building a hybrid system in my basement for winter and looking at raft designs. Did you go with the lip idea, and have space under the rafts? Pic's would be great if you had them, and any commentary on what is or isn't working out for you would be very much appreciated.
Cheers
Aug 28, 2012
Tray Rasco
I understand it is called Floating Raft system. However I have been thinking about a fixed height with maybe some 1/4inch plywood painted with a marine based paint or fish safe paint and backed with some 1x2 strips to prevent sagging. I would then use a standing drain pipe to control the height of my water much like you would in a pond. This would allow for plenty of air no foam touching water to create algae.
Sep 9, 2013