We made a visit to see how our system was doing in Locavore the other week, and are pleased to see things are getting along swimmingly. Both goldfish are growing, the tomato plant is producing fruit, and some fava beans and basil have taken up residence in the other grow beds.
Here’s a video shot a couple of weeks after the fish were added – thoroughly comfortable in their new home! You’ll notice that some paper was put in back of the tank to lower the amount of sun it gets – this will help control the temperature.
Although we originally planned on cycling this system with ammonium chloride, we found it difficult to establish a bacterial colony this way. This could have been due to a number of factors, but the algal bloom halfway through cycling potentially had a big part to play in it. In the end, we decided to cycle it using fish, and this proved very successful. While it can be risky cycling with the fish to start, as conditions have to be suitable to keep the little guys alive, in this case it presented the quickest way to get the system up and functional sooner, as significant delays were proving detrimental to the start-up process.
The system still needs to ramp up to its full potential – another couple of fish, and plants in all of the grow beds – over the next few weeks. And hopefully soon we’ll be able to harvest the plants and sell them in the shop with the rest of the local produce on offer! The Locavore system was our first, so there are lots of valuable insights to be gained from it. We’ll continue to monitor the system to gather data and help Locavore where needed, but in the mean time it’s on to our next project! Stay tuned to find out what we’re working on next…
We’ve spent the past few weeks cycling our system to build up a biofilter. The biofilter is the key to a successful aquaponics ecosystem – it’s the bacteria that turns the fish poo into fertiliser for the plants. The fish produce waste in the form of ammonium, which is then converted by the bacteria nitrosomonas into nitrites. The nitrites are converted by nitrospira into nitrates, which provides a delicious and nutritious meal for the plants.
The cycling sounded fairly straightfoward:
Step 1: Add ammonia
Step 2: Stuff happens
Step 3: Success!
But it’s proving a bit more tricky than anticipated. First we tried to cycle the system using ammonium chloride, which is a powdered form of ammonia. The advantage of this method is that there are no fish or plants at the mercy of volatile bacteria colonies. However, as we cycled over a few weeks the bacteria colonies never really seemed to settle in, and recently seemed to have left us altogether.
So I decided to go for a more hands-on technique – cycling with the first few intrepid fish. Cycling with fish means you don’t have to introduce any outside chemicals into the system, as the fish produce the ammonia themselves. It means you have to keep a closer eye on the system though, to avoid fish martyrs. When I showed up at the shop today though, the system was looking pretty grim – an algal bloom had struck!
I reckon it was a bit of a viscous cycle: the algae clogged up the pipes, cutting down water flow and leaving conditions better for more algae to grow, which completely stopped the taps this afternoon. The tank is also getting a lot of light where it is, so we’re going to cover up the window-facing side to cut down on sun and give the fish some privacy.
The fish had only been put in this morning, but there was no way they could stay in there. It certainly wouldn’t start things out on the right foot/fin.
We got them into a temporary abode, changed the water, and cleaned the algae off. The water can sit over night to let the chlorine evaporate (Glasgow’s tap water is actually quite good pH-wise and there isn’t much chlorine in it, but it will still have a bit) before reintroducing the fish to their home. For a more in-depth explanation of the cycling process, check out theaquaponicsource.com.
Here’s the system, sans fish. That trooper of a tomato plant has been there since the beginning. Looking a bit yellow at the moment without any nitrates, but still throwing out a few flowers. Can’t wait to see it flourishing in a few weeks!
On an equally rainy Friday, I made my way to Nithsdale Street to assemble the micro-aquaponics system in Locavore. There was nowhere in Glasgow that sold the size of irrigation piping I needed (not yet, anyway…), so I ordered it online along with the connecting pieces. The wood was provided by Locavore, freshly sealed with linseed oil, and the zip ties were kindly donated by a bike shop I stopped into on my way there (thanks to Willy Bains!).
Here is the configuration of piping that I used. 13mm sizing:
The upper pipe has three nozzles, one for each of the bottle rows. They will slide right into the holes that were drilled into the bottom of the bottles previously. As you can see, it’s just straightforward connecting the pieces. Putting my playschool skills to good use…
Next I attached the piping to a wood frame using saddle brackets, and secured the bottles onto the nozzles with the zip ties. Yes, a few zip ties were lost by messing around with them and zipping them too early. I’m pretty sure that’s the nature of the beast.
In the neck of each of the bottles I also put a small bit of sponge. This will help regulate the flow and also filter out any large particles that would otherwise cycle back into the fish tank. An old Irn Bru bottle provided the water catchment area to guide the water back into the tank.
I went to turn the system on and…the pump wasn’t strong enough. Womp womp. The tank I got off of Gumtree came with a pump, but it was old and most fish tank pumps are not tasked with pumping the water straight up nearly a metre. After a trip to The Aquarium on Chilsholm Street (just off of the Trongate) and a chat with the very knowledgeable owner there, we got a stronger pump, took it home, and voila! Three healthy streams of water. a sight to behold, if you ask me (video content and quality will improve, I promise. Still, a decent illustration, for those of you following along at home):
Stay tuned for next time, wherein we cycle the system to grow bacteria and introduce plants and fish to their new symbiotic home!
So there I was, tasked with a small-scale model aquaponics system for a local food shop, in a new city. I want to source as many materials as I can from recycled materials and local businesses to try and support local economy. At the moment, unfortunately, many of the materials needed to build the systems aren’t readily available without ordering them online. Hopefully as aquaponics becomes more popular, that will change. In the mean time, I’ll be sure to highlight any local businesses I do find that have a good stock of well-priced products.
First order of business was to source a tank. We decided to go with a tank rather than an upcycled barrel or IBC (Intermediate Bulk Container, more on these later) because of the small space we had to work with, and the way the end product would look. Because this is going to essentially be a window display, aesthetics are important. Also, because of its size, the fish will be ornamental rather than consumable, so we want to be able to see them. I got a 60L used tank off of Gumtree for £30, and went with 6 750mL plastic bottles to match. While the recommended tank to grow bed ratio is usually 1:1 (and can stretch to 1:2 for experienced aquapnicists) the bottle systems I’ve seen seem to stay on the conservative side, so I decided to go a bit rogue with the ratios. If the plants are overwhelmed with nutrients, we could always add new bottles.
So one rainy Thursday, we began our assembly. First order of business was to drill holes in the bottom of the bottles (this will be where the nozzle of the next bottle will go) and in the sides for the plants to grow out of. This proved more difficult than we had anticipated, given that plastic melts with the drill heat, and is generally a pretty stubborn material to work with in cylindrical form. However, we managed to get them drilled without too much carnage and spray-paint the bottom (this will discourage mildew and algae growing in the clay substrate).
They may look a bit flimsy, but the bottles have held up very well so far. In the future I’d like to get a plastic cutter so that the lines can be a bit neater, but overall they seem to be doing the job. And they’ve got that added rustic element that the cool kids love these days.
Next order of business, piping and framing and pumping, oh my!