Can Planted Aquariums Contain More Fish?

All aquarium habitats will benefit from live plants. The best way to get into fish keeping is to start out with plants and allow them to ease the habitat into the nitrogen cycle until an aquatic ecosystem can be established. Plants will continue to take important roles in terms of optimally adjusting the biochemistry of the ecosystem, which means planted aquariums have a great potential of making aquatic habitats healthier for all species. As to the question at hand, freshwater planted aquariums can make it easier to support a heavier bioload, which means they can hold more fish, but there are some caveats in this regard.

More Fish Isn’t Always Better

The healthiest aquariums are large with a nice diversity of plants and not many fish. For example, many aquascaping hobbyists only keep a school of about 10 to 15 neon tetras in a 50-gallon tank even though they know their aquariums could easily support a school of more than 50 neon tetras. You should have more plants than fish in your tank.

Aquatic Plants Are Natural Filters

In a fish tank, the water isn’t kept clean by the filtration and aeration systems. This is the function of plants and bacteria that feed on toxins and harmful chemicals generated by fish waste. What the mechanical part of a filtration system actually accomplishes is keeping the water clear. When you have a tank that registers upticks in ammonia levels just a few days following a partial water change, the ecosystem will benefit more from adding plants than installing more filters. This is the reason planted tanks can hold more fish compared to those without plants. It’s because they actually serve as purifiers more than filters.

Bioload Calculators Are Never Accurate

You can go online and find many websites that offer bioload calculators based on certain parameters, but nearly all of them produce results centered around the “one inch of fish per gallon of water” rule of thumb. Marine biologists will tell you it’s nearly impossible to accurately figure out the bioload of an aquarium. That being said, it’s safer for you to go over one inch per gallon if 25 percent of your tank is occupied by plants, but never more than 1.5 inches, and you should always keep an eye on ammonia levels, and don’t forget to add biological media to your existing filtration system.

More Plants Than Fish

Whenever possible, try to tip the balance of aquarium species toward plants. A 20-gallon tank that’s planted like an underwater jungle won’t support an Oscar, but it can certainly hold guppies, mollies, neon tetras, Corydoras, and shrimp. Even if you feel confident with overstocking a tank, you don’t want to run into a situation whereby a high bioload turns into constant algae bloom. The more fast-growing plants you have in your aquarium, the less algae you’ll have in the tank. Remember the phrase “balance planted aquarium.”

Even with the right balance of plants and fish in your tank, you’ll still need several key supplies to maintain the aquarium properly. You can find everything you need at Aquatic Warehouse, a leading provider of freshwater and saltwater aquarium supplies. Stop by our store located in Kearny Mesa, order what you need from our website, or give us a call at 858-467-9297 if you have any questions.