Backyard Aquaponics
A place to discuss aquaponics

Ok here is the scoop. I am not able to erect a structure over 120sqft without building permit and run into huge requirements. Anyway I came up with a plan to make 119sqft units.

The plan is this.

6 barrels per unit.
12 barrel half per unit will fit with comfort.

Now what I am wanting to know instead of doing gravel medium I am wanting to take a different approach. I have seen many of studies about growing without medium floating the plants above. So instead of building a frame like I have seen I figure I can take barrels. I will link them with maybe a 8 inch bulkhead. Flow water through them

You wind up with 4 barrels linked together via bulkhead. This allows for the water to flow through at higher velocity. I figure if I take this cut styrofoam to fit the barrel tops suspend plants with.

Now my question is the barrels will be on the ground. They will have water flowing through them all the time. How do I prevent the growbeds from overfilling and how do I prevent the actual water reservoir from overfilling?

I cannot seem to work out the pipe/pump configuration needed to do this. It seems to me that it will be cheaper than dealing with building a frame and then lining the frame with PVC liner, welding the pvc etc.

I hope this explains my plan but I will have 3 rows barrels 4 long in each unit linked to a central reservoir. Size of this Reservoir is to be determined yet based on how many units I want. I am thinking on the order of 5 units. This would be a total of somewhere around 2600 gallons in grow bed alone.

Thoughts? Comments? Pipe Masters please!

Note: Forgot to mention they will be structures that in the summer are covered with shade cloth to prevent blistering heat. In the winter they will be covered with Greenhouse film.

How are you going to deal with biofiltration if you are not going to use media in the grow beds? That is where the real need for a particular amount of GB volume is usually figured, the amount of gravel to provide enough surface area to take care of the ammonia/nitrite. I know many people are looking into fluidized sand bed filters to get more bio surface area but then you also need to deal with solids.

I don't know how much you are paying for barrels if anything but EPDM liner in a wood frame on the ground can be built to size so you can reduce the number of plumbing fittings needed per SF of grow space. As I worked it out the liner in wood frame was less costly for me than what I would need to plumb up and support the same amount of GB volume in barrels when my cost for barrels in $15 each.

As to how to keep the barrels from overflowing. I expect you would need a few overflow pipes or stand pipes to keep the water level from getting too deep. I'm a little confused about your question about keeping the reservoir from overfilling. If you have a tank lower than the grow beds with a pump in it, it pumps up to the grow beds and then can flow through the overflows back into the tank. It should all stay pretty constant level (other than evaporation or disaster) if that is all there is to it. Of course if the barrels are on the ground, then it gets more difficult to have the tank lower than the barrels unless it is sunk in the ground.

Oh, just an FYI, I found an easy way to support two barrels side by side was on a pallet flipped upside down, though this probably doesn't really help for the layout I think you are talking about.

Back to the topic at hand. If your reservoir is going to be higher than the grow beds, it is pretty easy to set an overflow from the reservoir into the grow beds but then you need a second tank to act as a sump and lift water back up to the reservoir after it drains from the overflows on the grow beds.

Again having 2600 gallons of grow bed that have no media kinda begs the question of how are you going to deal with the bio-filteration? To support enough fish to provide nutrients to 2600 gallons worth of plants, you are going to need a huge amount of surface area of media some where as well as some method of dealing with solids.

Biofilter yes that is a good question.

http://www.pubmedcentral.nih.gov/articl ... id=1448996

I wonder if it would be too difficult to do something like this?

The water volumes they are using are much higher however so I should be able to get away with much smaller than they are using.

I agree with TCLynx, whilst the barrels are cheap the fittings are expensive.

to support half barrels, i used two pieces of wood bolted together in the center to form a cross. by using two crosses one at each end the barrels can be supported nicely. For a pic see my duckaponics system in members systems. (sorry i dont know how to link to it)

why do you not want gravel medium? it works well, and gravel is cheap or even free, it seem to work better than the NFT systems

I don't want to deal with disposing of that much gravel if I move.

I'm not sure but at a quick glance on that link, it sounds something like an RSG (really smart guy) filter. I don't know that it is what you want in order to grow veggies since they tend to release Nitrogen as gas rather than converting the Ammonia to Nitrate. They are a way to get rid of the Nitrogen load when you don't have enough plants to use it. If you are planning a huge amount of plants in your DWC barrels, you need the Nitrogen. You might look more into fluidized sand bed filters and some additional solids filtration. But then again, if you go with gravel, it doesn't have to be a big deal to get rid of it. Probably just spread it on the ground and call it decorative if you move too far to think of taking it with you.

http://www.highdesertkoi.com/filtration.htm looks neat as well.

$150 for a blower that only used for cleaning the filter from time to time. Ouch.

Depending on the amount of fish you are planning and the types of plants, you might be able to go the koi filter method. It is really meant of ornamental koi ponds though and might not handle enough fish load to supply the amount of plants you are talking about. I'm not an expert in these methods so I'm not sure.

With the mechanical solids removal, you are pulling out some of the nutrients you may need for flowering or fruiting plants so you might be restricted to plants like lettuce.

What are your goals with this system?

Sounds like a job for the trusty shop-vac on blower

My shop-vac is actually my favorite tool! I vacuumed the lawn with it once; ground up leaves with the mower then sucked them up and put them in the compost bin.

Them suckers do come in handy

LOL they are insane no? I would build it myself obviously and use my own blower.

I was not willing to buy grow lights and built my own from parts... yep saved about 800$ people are bloated full of insanity I say.

What Kind of Growlights are you talking about?

I am running 2000watt of metal halide in the garage. It is x2 1000 watts. I have about 200sqft of area out there