Initial Forays into Aquaponics

I’ve spent a bit of time studying hydroponics and aquaponics . . . learn something new every day.  There are a couple places I would suggest you spend some time if you want to read up on aquaponics.  The first is the Back Yard Aquaponics forum.  A lot of the folk there are from Aussie Land, but there is also a smattering of other folk, including some hardy Americans (go USA!).  The second is the Yahoo Barrelponics group.  You will find a wide variety of stuff therein.

Before you read any further, I’ve changed my approach on this, though the post is still thought inspiring.  I have switched to a single protrusion auto-siphon setup.  To see how that was constructed, look at the auto-siphon page (link located in the menu).

I am working on a prototype single barrel system for inside my sun porch.  Once I have done my experimenting I will build a system for my mom.

The system pictured to the right is based on the brilliant work of Travis W. Hughely (listowner of the barrelponics Yahoo group).  It uses a combination of toilet tank parts, water bottles, pumps and piping to craft a small footprint aquaponic grow bed suitable for placing inside a south facing window.  Pretty brilliant, but I can never leave well enough alone.  There are SO many roads to Rome and I’ve got to flirt with them all.

I’ve been considering what I want/need/desire, and I want to play with a slightly less complex system.    A few parts, strategically crafted, a good quality pump, a good quality timer and I should be good to go.  So this is my plan

Using a single barrel, two Uniseals (1″ and 2″ or 2½”), a short length of 2″ or 2½” PVC, a slightly longer length of 1″ pvc, an 1″ pvc elbow, a bit of screening, a bit of large diameter clear pipe, some gravel, a good quality pump, a good quality timer and I should be ready to play.

First I have to craft the components.

The first item on the left is a screen to keep the grow bed medium (pea gravel) out of the overflow/drain.  The screen is an inch taller than the overflow (same height as gravel).

The second item is the drain rate adjustment tube, hereto after known as the drain valve.  This tube is 2″ taller than the sides of the grow bed and is raised or lowered to control drainage.  The holes around the top are to allow water to flow over the top of the overflow (next component) into the drain tube. The arched opening in the drain valve allows for the valve to clear the fill tube and be fully seated on the overflow/drain tube.  The arch will accommodate the horizontal bit of the fill tube.

The overflow tube (Uniseal installed) stands 2″ shorter than the height of the grow bed when installed.  The overflow/drain tube has opposing holes.  The visible hole is at the bottom of the tank and allows the water to drain out of the bed at the rate prescribed by the drain valve setting.  On the opposite side is another 1″ hole about 2/3 of the way up from the bottom of the tank through which the horizontal portion of the fill tube will protrude.

The last item is the fill tube.  It is dry assembled and installed inside the overflow/drain tube with the horizontal bit sticking through the side using a 1″ Uniseal.

These items are nested to create a compact control center in the bed.  Once assembled, the image to the right is what the gross component will look like. The fill tube in the center is connected to the pump.  Any water draining will bypass the fill tube and drop into the tank.

I’m anticipating planting a ring of plants around the outside of the bed, and another smaller ring or a single larger plant on the inside.  Placement of the intrusion into the bed should not interfer with that plan.  Because of the compact design I should be able to maximize the planting space.

The pump is the only attachment at the bottom of the bed.  A dry fit pvc tee/adapter will accommodate a valve to adjust flow to the grow bed.

The pump (submersible) and flow control valve will be inside the fish tank portion of the barrel.  If the valve is wide open, the majority of the flow will immediately return to the tank.  As the bypass flow is restricted more water will be routed into the grow bed.

I need an suitable programmable timer to run the pump.  I’ve looked at a couple different types, from the max simple (inexpensive) to the way more complicated (small mortgage required).  I think more research and testing is required.

I’ve covered all the gross stuff.  There are some nit-picky details yet to be worked out:

?I have to have a screen over the fill tube course enough to allow fish tank debris unrestricted passage into the grow bed yet with small enough mesh to keep the grow bed medium out of the pipe.

?Will the dry fit pvc parts stay together under the force of the flowing water?

?Will the overflow/drain pipe be big enough to allow disassembly of the horizontal pipe from the elbow so the horizontal pipe can be removed from the Uniseal?

?What’s the best material for the screen around the assembly?  It’s got to be stout enough to keep the grow bed medium at bay and stout enough to allow the hole for the fill tube stub to stick through to be cut.  I may have to braze a wire around the opening to stablize it.  We’ll see what I find to use.  I’d love to use stainless steel screen of I can find some.

I’m going to try and get a barrel and the basic (inexpensive) parts this week.