Imagine a stranger came up to you holding a bag of fish from the pet store and said, “Hey, you! Did you know you can grow a garden using live fish?” It’d be a little unsettling. But now imagine it’s me, your trusted gardening friend Amanda grinning at you while holding a bag of betta fish saying the same thing. I’m not selling this, am I? But it’s true! You can grow an aquaponic herb garden using live fish! But before explaining how to create an aquaponic herb garden, I feel like we should back up a bit and talk about what the heck aquaponic gardening is in the first place. You know, to renew your trust in me.
What is aquaponic gardening?
Aquaponic sounds similar to hydroponic because they share the same suffix “-ponic” which literally means “to labor with ” or “to work on.” With hydroponic gardening, water is the prime element working to grow plants. With aquaponic gardening, fish (swimming and pooping in water) work to grow plants. An aquaponic system mimics a natural ecosystem, forming a mutually beneficial relationship among fish, plants, water, and the bacteria and nutrients shared between them. Waste by-products from the fish (fish poop) become food for bacteria, which serve as fertilizer for plant roots. Plant roots absorb that bacteria which cleans the water for the fish.
How to create an aquaponic herb garden using any fish tank
Aquaponic systems can be created in large aquariums and yield big garden beds. But for smaller spaces and home use, an aquaponic herb garden can be made in as small as a large mason jar (64oz+) could even work, though not recommended. However, if you do have a smaller tank (3-5 gallon) betta fish are preferred since they are not a schooling fish, meaning they like being on their own. They also prefer smaller spaces, so they don’t mind living in a smaller tank.
Here are the basic materials you’ll need:
- 3-5 gallon fish tank (or larger)
- Betta fish: The best type of fish for a smaller set up
- Herb plant: Wheatgrass can grow just being sprinkled with clay pebbles (sold in aquaponics stores). Or, for other herbs, they could be started in rockwool. Basil and coriander are excellent choices because they are leafy.
- Topper: You will need to cut or drill a hole in a top that will sit on top of the tank. From there, you’ll add a net pot (below).
- Net pot: This is what it sounds like, a small cup with holes in it, available at your hydroponics store and online.
- Growth medium: This is what your herbs will grow in. Clay pebbles, lava rock, and expanded shale make excellent choices for an aquaponic herb garden.
- Water: A test kit will be helpful too, to make sure it’s ideal for your fish.
- Airstone and/or air pump – these add-ons help circulate and disperse oxygen. If you choose not to use these, you’ll need to change the water every couple of weeks.
- Decorative fish gravel – if you decide to use it, don’t use more than an inch or so, otherwise, it’ll take up too much space.
- Clean and rinse out the fish tank.
- Add clean, decorative gravel and airstone/pump to the bottom of the jar, if desired.
- Fill the tank with water. If you use tap water, use tap water conditioner for fish.
- Acclimate your betta fish to the jar. This may feel like a lengthy step, but it’s the best way to successfully acclimate a new fish to your aquaponic herb garden without having a “burial at sea” fishy funeral. Start by putting the unopened fish bag into the tank and let it float there for 20 minutes. (Note: this may displace a bit of water so you may need to top off later.) Then open the top of your fish bag and scoop some jar water into the fish bag. Add about as much water as there was in the bag so that the volume in the fish bag has doubled. Wait another 20 minutes. Now the tricky part, using a net or scoop, remove the betta fish from the bag and place it in the jar. It’s important not to mix the water in the fish bag with the jar. The reason behind this is that there is a higher risk of disease from the pet store water which can not only affect your fish but also the aquaponic herb garden. Top off the jar with distilled or purified water leaving an inch at the top.
- Wait a few days to a week before adding your herbs. This allows fish waste like nitrogen to build up so that your plant will get optimal nutrition right away.
- Add your cover to your tank, and lower your net pot into the hole you’ve created, with roots touching the water, or add your growing medium topped with seeds.
Once your aquaponic system is up and running there’s little you need to do, other than naming your fish something adorable and talking to them while making your morning coffee. The herb and fish will provide nutrients for each other. If you don’t set up a simple AirStone or air pump with tubing, you will need to change the water every couple of weeks. Harvest your herb leaves as needed, taking care not to deplete the plant fully. And be sure to tell Squiggly I say hello!
Have you ever made an aquaponic herb garden? What are some of your tips and tricks? Let me know in the comments!