It is November and temperatures are dropping below zero (centigrade) already, I need to move the fish from my balcony aquaponics system (as introduced here) indoors.
Instead of putting them in a common aquarium with a standard filter, I decided to build an indoor-aquaponics setup instead. As this system will be located in my apartment, appearance and design are equally important as functionality. Therfrore, I decided to build the system based on an ikea shelf that matches my other furniture.
Take a look at the technical demonstration in this youtube video here:
- 1 Ikea Besta shelf (120x40x40cm) or any other shelf according to your preferences - €20,-- (2nd hand from willhaben.at)
- 4 furniture wheels plus screws - €25,-- (Obi)
- 1 Aquarium (max 110x35x35cm - in my case 60x30x30cm equalling 54 liters) - €10,-- (2nd hand from willhaben.at)
- 1 aquarium pump (I ordered the smallest one I could find on Aliexpress.com, 200l/hour, 3W) - €4,--
- 50cm Aquarium tube (8mm) - €1,--
- 30cm standard pvc-drainage pipe (25mm) plus matching uniseal - €3,5
- One or two 100cm flower box for balconies - free
- piece of wood to screw the wheels on
- white wood color or duct tape
- hydroton (or other media for the grow bed)
I like the idea to reuse and recycle, therfore I tried to use as many 2nd hand parts as possible.
- jig saw
- screw drivers
- elctric drill
- ruler, sharpie
- whole saw bit (matching the diameter of your drain pipe)
With this, we are ready to start our build.
Step 1: Dismantle the Shelf
Disassemble the shelf (given you use one that has been assembled already) by losing the plastic screws at the inside of the three vertical side-panels. Take the top-panel off, then the three side panels.
Step 2: Cut the Shelf Into Suitable Pieces to Fit the Fish Tank and Plumbing In
We need to adopt the shelf a little in order to fit the fish tank and the plumbing in.
Let's start with the main compartment for the fish tank: To do so, draw a mark at the second vertical panel (the one in the middle of the cabinet) 4.8cm from the back-facing end. Cut the panel in two pieces with your jig saw. The smaller part (4.8cm wide) we will use as support beam at the backside of the shelf as shown on the picture.
That was the tricky part for me, as I was not sure about the material and inner structure used for the panels. Turns out that it consists of two layers of 5mm chipboard filled with paper in a honeycomb structure as support.
I was afraid that the saw could destroy or at least destabilize the remaining parts but that was not the case. At the pictures you can actually see, how the boards are built and that it is no problem to cut them as described here.
Now we need to cut holes in the top panel. At first find the appropriate places for the holes to be cut by placing the flower boxes on top. You want to have your flower boxes covering the holes in the end, so experiment a litle to get everything in place as you like it. I figured out, that two rectangular holes (20x8cm) work best for my flower boxes - big enough to access the fish tank from the top and small enough, to remain completely covered by the grow beds. Mark the holes and use your drill bit to cut two holes and then extend it with your jigsaw to its final rectangular shape.
Finally, I used a 5cm drill saw bit to cut a couple of holes into the upper end of the two thin back panels of the cabinet. This allows some light in and allows also to put the power cord for the pump in.
At first I planned to paint the sides of the panels I with white paint but then found a roll of white duct tape - much quicker and easer to apply!
Step 3: Re-assemble the Shelf
Put the two side panels back in, then the support beam we cut out of the third panel. This goes at the back side of the shelf. Put the two back chipboards in. Mount the top panel.
Then turn the whole cabinet upside down and mount the wheels. We want to avoid to directly mounting the wheels on the bottom panel because of the limited amount of support structure the chipboard provides to the screws. Therfore I put a thicker piece of wood in between which I screwed into the already availabale threads Ikea put in to mount legs on the shelf.
Step 4: Plumb in the Fish Tank and Install the Grow Beds
Put the aquarium into the cabinet. Now we can assemble the grow beds. To do so, we need to cut holes in the bottom of the flower boxes using the hole saw bit of our power-drill (I use a 30mm bit which is the perfect size for my 25mm pipe plus the uniseal).
Put your unisieals in the holes and then insert the pvc-pipes. Due to the small dimensions of the system, I decided not to add a syphon to drain the water out completely of the grow beds but to have only a pvc-standpipe which will keep a constant water level in the beds. You want to experiment with the height of the standpipe within the growbed. I mounted mine 4cm from the bottom of the growbed. This leaves another 10cm to the top of the growbed to aerate the roots of my plants. To protect grow media from falling through the standpipe, I added a media guard made out of a small white plastic container (actually an old bottle of vitamin pills). I cut out the bottom with my hole saw bit and lots of 6mm holes at the sides. I also drilled a hole in the cap to run my water tube trough.
Technically you are now done with your project. Add the pump, water, grow media, plants and fish and your ready to go!
As to the pump: I wanted to mimimize energy consumption, therefore chose the smallest pump possible - a 200l/h 3W pump with 50cm head height. I figured 50cm would be enough to lift the water up into the grow bed. Also, to simplify plumbing, I ran the water tube from the pump into the grow bed through the drain pipe. Therefore I did not have to cut any additional hole. So far it works great. I'll need to see over time, if the pump is strong enough or if any cloughing caused by fish waste occurs. In this case I would upgrade tho a biger pump and tube diameter.
Good luck with your project and thank your for posting your comments & questions!