Last weekend I had another one of those wild ideas that suddenly just manifests in your brain when you look at something. A little light goes off and you wonder why that thought never crossed your mind before. We get a lot of those around here. Pure moments of genius. Well, in our world anyway. And we always share them with one another in an almost apprehensive way; knowing what we’re about to say could sound totally insane when it’s out of our mouths. It’s always prefaced with one of us stating, “So I had this crazy idea…”
We’ve been thinking and talking about aquaponics systems for well over a year now. But we were always kinda scared to jump in because it all seems so complex. And when I say “we,” I completely mean “Stefan” here because things of this nature are really his territory. I am merely the assistant who does her best to make the process go smoothly (finding tools, parts, setting screws, finding screws, etc.)
If you’re reading this and wondering just what aquaponics even IS, it’s a fairly simple concept. Water from a fish tank feeds into a growing bed with aquaponics pebbles in which lettuce, tomatoes, herbs and just about any other sort of vegetable can be grown. The fish waste fertilizes the plants and you only have to feed the fish. You can grow worms or other plants just for the fish as well so everything is self-contained and self-sufficient.
The previous owner of our farm apparently used to have some free range ducks at one point…or at least that’s our guess about the mini-pond by our mudroom that once had a wooden ramp leading into it was in its hay day. It’s about 5 feet x 4 feet and a couple feet deep.
So I walked by this pond for the millionth time and I thought, “We should turn this into a food and fish growing paradise.” Then I turned to Stefan and asked, “Could we use the pond as a sump tank for an aquaponics setup?” Because I’d learned at least enough about aquaponics by then to know what would and wouldn’t work.
The gears in his head started turning and he quickly was obsessed with the idea. And so it began.
We decided to construct a platform directly over the pond which will be our primary grow bed. Finding a suitable plastic container to use for beds was useless so we decided to build the entire thing by 2″x2″ timbers and outdoor decking boards which we’ve used for other projects like our pump house and outdoor patio furniture.
We decided to use the IBC tank that we already had in the courtyard for rain water storage as our fish tank. That meant draining about 750 liters of water from it, most of which we were thankfully able to save for the sump tank and the refill of the fish tank.
Costs so far (in Euros)
|2″x2″ Construction Beams||44|
|120x180cm Plywood floor for grow bed||15|
|Pond foil 2m x 4m||31|
|Hoses & connectors||15|
I’m going to go into a lot more detail about what we’ve done and built, which will hopefully be useful if you want to do something yourself. After 2 days of work (which included an excursion to the home improvement store for supplies), we’ve built the frame, floor and sides for the grow bed, put in the pond liner, built a drain, moved the IBC tank, hooked up the pump in the sump tank and set an overflow pipe from the fish tank to the grow bed.
We’ve still got to cut a larger hole in the top of the fish tank and will probably build a small grow bed to sit on top of it. This will cut off some of the light to the tank and also make it a little bit safer when little people learn to climb up the cage. Mackenzie was already trying that yesterday.
We also need a couple hundred liters of hydroponic pebbles, a frame to hold the pond liner in place and will eventually build some additional hanging wall channels with small pots of pebbles in them. We’re currently planning to grow cooking herbs, lettuce in the summer months when the salad table dries out too quickly, bell peppers and other goodies in the grow box. We’ll probably do strawberries on the wall.
We’re not sure what fish we’ll put in there yet. We’re considering tilapia or catfish…and may couple them with crawfish. But we also have to start thinking about a place for a breeding tank since it will get awfully pricey to keep buying fingerlings to eat…and with the right conditions these fish will breed like crazy.
If you’re thinking about starting an aquaponics setup, check out the first part of my aquaponics how to. Although it can be really difficult to find decent instructions about how to build your own aquaponics system, I hope we can shed some light on our process which may explain things. And since there’s bound to be problems at some point, you can learn from our mistakes too. 🙂