Whether you’re a long-time veteran of the aquarium hobby or a first time fish keeper, there’s a good chance that aquaponics are something you’ve never tried before. These fish tanks combine the worlds of gardening and fish-keeping into something like what we see in nature.
Plants, people, and fish come together to form sustainable ecosystems that provide for each other. And best of all, these systems can be created even in the smallest of tanks and apartments!
Advantages of Aquaponics Systems
Aquaponics are fascinating because they make the nutrient cycles of the natural world that much more obvious. In your own home you can see how plants nurture animals and vice versa while partaking in the literal fruits of their endeavors!
But don’t think you stand apart from the miniature worldly cycle. You even participate in the process through your exhaled carbon dioxide and the care you provide both your plants and aquatic animals.
The basics of the system is that as fish feed, they produce ammonia and other nitrogenous waste products. Instead of running a filter in an aquaponics fish tank, you have a pump that sends water into a plant tray, usually placed overhead but sometimes to the side.
Soil bacteria perform the same function as nitrifying bacteria in a standard filter. They convert ammonia into nitrite and nitrate, detoxifying it before the water is returned to the aquarium. Plants also uptake all three chemicals as food as well as some of the water pumped into the growing tray.
Indoor Gardening
Aquaponics are ideal miniature gardens for apartment dwellers and other space-limited people. While everyone wants an outdoor garden bed not everyone is blessed with the climate and land to do so.
Indoor gardening is also entirely pest-free, with no caterpillars or other insects sweeping in to devour your hard work. And if you prefer to grow flowering or other ornamental plants, your aquaponics system can become a decorational feature or conversation piece suitable for any room layout.
Educational
Most kids are highly interested in science. Aquaponics are a great way to teach kids about nutrient cycles and the inter-relations we all share between our biology and the environment.
What could be more obvious than watching water flow from an aquarium into a plant tray, and seeing vegetables and fruits develop from the nutrients they take in? You’re not only planting literal seeds but also ideas and interests that might flower later on in your kids’ futures!
Difficulties of Aquaponics Systems
Here are a few of the drawbacks of aquaponics systems:
Space Consuming
Aquaponics are much smaller than koi ponds or outdoor gardens. However they do take up significantly more room than a typical aquarium or bowl. The light, overhead tray, and other items can double or even quadruple the footprint taken up by the setup.
Delicate Ecosystem
Since the fish depend on the plants and the plants depend on the fish, a failure in one end of the equation can cause problems for the other. The nice thing about a typical filter is that it’s easy to change the media, add bacteria, and otherwise get it quickly operational.
But plants can take days to weeks to adjust to issues that arise. Fortunately, there will be few to no issues as long as you have proper lighting, substrate, and nutrients!
Setting Up an Aquaponics Fish Tank
Aquaponics fish tanks take a bit more research and time to plan and set up over traditional aquariums. However the benefits are clear: an educational, interactive filtration design and delicious home-grown produce to enjoy.
If you don’t care to create the stand, find a light system, and otherwise build the aquaponics fish tank on your own, consider picking up an all-inclusive system! Smaller models make fantastic gifts for kids and home office dwellers. Keep in mind that nearly all do still need a light source for proper plant growth, however!
Lighting for Aquaponics Fish Tank
All plants need light. But not all lighting is created equal. Even the brightest incandescent and fluorescent bulbs can be useless for plants because most don’t release the right spectrum.
Photosynthetically active radiation (PAR) is essential for plants because these are the wavelengths they use to convert water and carbon dioxide into the sugars they need to live.
Many aquaponics setups used and still use T5 fluorescent light fixtures that one can easily get from home improvement stores. These fixtures use multiple bulbs suspended over the plants to provide the radiation they need. Just be sure to choose fluorescent bulbs with the right spectrum!
Nowadays, LED lighting has become dramatically affordable and is slowly replacing fluorescents for most uses. LED bulbs run cooler, use less energy, and have comparable brightness.
On the other hand, fluorescent bulbs are usually cheaper to replace than LEDs. But the lifespan of LEDs is so long (10,000+ hrs) that this isn’t usually a huge factor.
If you’re looking to purchase an all in one aquaponics fish tank, read carefully to see whether it includes lighting and what sort. Some of the cheapest options use inferior lighting which won’t grow plants beyond the seedling stage.
Substrate for Aquaponics Fish Tank
Choosing the right plant substrate is the next most important factor in an aquaponics fish tank. The two most obvious choices, gravel and potting soil, are both some of the worst for most aquaponics setups!
Gravel is solid rock and has no capacity for nutrient and water storage. Both run right through the substrate to the bottom and back into the tank. Unless you’re pumping in water constantly, your plants won’t get much to drink or eat.
Soil, on the other hand, can liquify or turn to mud if too much water is added. In a slower drip-based system it can work beautifully, especially in a dry climate. However, clay pellets and soils tend to work best for indoor aquaponics because they have the ability to store water and nutrients over time.
Clay has a very high cation exchange capacity (CEC). This basically means that it acts like a sponge, latching onto nearby elements until plant roots extract them.
And while clay holds onto water and nutrients the larger grains allow plenty of airflow as well. Clay pellets create the perfect root microclimate for aquaponics grown plants!
Best Plants for Aquaponics Fish Tanks
Here are a few of the best plants for aquaponics fish tanks:
Herbs
Culinary herbs are some of my favorite plants to grow in an aquaponics system. They don’t have a seasonal fruiting or flowering period so you’ll always have leaves or stems to snack on.
Some of the most common aquaponics herbs include Basil, Thyme, Rosemary, and Lavender. Keep in mind that many herbs are of Mediterranean origin, which means alternating wet and dry periods. Rosemary and Lavender don’t appreciate being soaked year round as they are prone to root rot.
You’ll also want to consider using a citrus, palm, and/or cactus soil blend for them. These soils tend to drain much more quickly, ensuring the roots remain aerated and dry rather than waterlogged.
Tomatoes
Ahhh, who doesn’t like garden-fresh tomatoes? Tomatoes are not only delicious but look incredibly attractive at all stages of their growth.
Tomatoes do prefer intense lighting and warmer temperatures so make sure your home has a room temperature warm enough to encourage them to grow and fruit.
Tomatoes are ideal aquaponics plants for fish-heavy systems because they love loads of nutrients. Heavily stocked aquariums will provide more than enough for them to thrive!
Strawberries
Small, flowering, and delicious, strawberries are a popular choice for any aquaponics system. They are instantly recognizable to even non-gardeners and produce fruit relatively quickly.
Strawberries do prefer cooler climates than some other plants; they can be difficult to grow alongside tomatoes, peppers, and other heat-lovers. So choose your varieties carefully to ensure compatibility!
Conclusion
I highly recommend aquaponics fish tanks if you’re looking for something a bit more unusual. They are excellent for aquarists that are space or climate-limited yet still crave a bit of greenery to care for. And the mutual dependency of the plants and fish on one another creates a fascinating dynamic that’s far more engaging (and delicious) than a standard mechanical filter!
