I prefer an aquaponic garden over a traditional soil-based garden. There are a few big advantages aquaponic gardens have; there are a few minor drawbacks, too, but I think they are pretty manageable.
What is Aquaponic Gardening?
Aquaponic gardening (or aquaponics) is the intersection of aquaculture (raising fish) and hydroponics (growing plants without soil). It’s the same idea as the betta fish in a bowl with a plant in the top. You feed the fish, the fish poops in the water, which feeds the plant. The plant using the fish poop as nutrition cleans the water for the fish.
If we take the fishbowl idea, scale it up, and replace the pretty houseplant with vegetable plants, we have an aquaponic garden. Make it even bigger and it’s an aquaponic farm.
My Aquaponics Experience
The most effective aquaponics setup, in my opinion, is called CHIFT-PIST, an acronym for Constant Height In Fish Tank-Pump In Sump Tank. It consists of two tanks, fish tank and sump tank, and the grow beds – the places where the vegetables are planted. Different grow bed types are appropriate for different types of plants. For example, leafy greens are entirely appropriate to grow in a floating raft system where the plants are suspended with the roots dangling in the water.
I set up a 100-gallon fish tank with about a dozen goldfish and a 66-gallon sump tank (a Rubbermaid tote). The grow beds were re-purposed square-foot garden boxes that had the soil removed and auto-siphons installed. Lava rock and gravel were used as a growing medium. It worked out pretty well after I worked out the kinks. We got a few tomatoes and zucchini from it. The biggest issue I ran into was the heat. I had set the system up in a hoop house in Sacramento, California, and the greenhouse got really hot (well over 100 degrees F) in the summertime. I intend to fix that with my next greenhouse.
Aquaponics requires pumps to keep the water moving between the sump tank, the grow beds, and the fish tank. Of course, pumps require electricity. The power requirements can be managed using solar or wind power in order to keep recurring costs down.
A system like this requires a decent investment of money up-front. Mine cost about $200 to set up. I re-purposed some grow boxes and built the fish tank from a sink crate and some scrap plywood with a pond liner.
Filters need to be cleaned periodically, and the grow beds occasionally. The extra fish waste can be used to fertilize other plants, so it’s not a complete loss.
Some plants are not well suited to aquaponics. Root vegetables and tubers don’t do well in these systems. If they are your priority in gardening, maybe aquaponics isn’t a great idea for you. My preference is to use the fish waste cleaned from the filters to fertilize the plants in my outdoor garden in an effort to not waste anything.
Advantages of Aquaponics
There are some advantages to an aquaponic system, too. In my opinion, they outweigh the disadvantages. There is a great deal of good information on the web about aquaponics. One of my favorites is Bright Agrotech. They have a huge amount of great information as well as a super YouTube channel.
First and foremost, I have never had to pull a weed in my aquaponic garden. That by itself is almost worth the investment.
Second, these systems use about 5% of the water used in traditional gardening. Much of the water in traditional gardening is lost to other plants (weeds), runoff, and evaporation. There is some evaporation in aquaponic systems, but it is manageable.
If you choose to raise an edible fish, you can raise a protein source along with your vegetables. My plan with the new system is to raise catfish in two tanks. If I buy enough fingerlings to raise in one tank the first year, I can expand into the second tank in the next year without worrying that larger fish could eat the smaller ones.
I’ll manage an aquaponic garden over a traditional one for most things any day. I don’t need to stoop to harvest, and if I build it in a greenhouse, I should be able to get good produce all year long.