Growing aquatic plants and keeping a planted tank balanced requires a combination of art and science.
There are many philosophies on how to set up a planted aquarium, which makes it fun to experiment and find out what works in your own tank. Planted aquariums are not difficult but they do provide a challenge both in aquascaping along with plant care. Many tropical fish develop richer colors when kept with live plants.
If you’re thinking about setting up a planted aquarium, look no further. We’ll explain everything you need to know to get started.
There’s one important difference between a planted tank and a fish aquarium. The main focus is on providing what the plants need for lush, healthy growth. Fish are secondary but if you’ve set the tank up properly, your tropical fish will develop color patterns that can only be seen when kept with live plants.
Follow along as we take a bottom to top approach to setting up a planted aquarium.
Aquatic plants have a fibrous root system that anchors the plant and adsorbs nutrients from the soil. In nature the plant roots adsorb essential nutrients like phosphate, nitrogen, and sulfur from the soil particles. The roots also release chemicals that make trace elements like iron and zinc easier for adsorption. Regular aquarium gravel is too coarse and has no nutrients. Fortunately, specialty substrate like German-made Scaper’s Soil by Dennerle is the perfect size (C1-4 mm) to secure the plant roots and creates a natural-looking aquarium. The substrate is completely natural and contains essential trace elements that are extracted by the plant roots.
It’s obvious aquatic plants need water. But the kind of water makes a big difference. Most tropical aquatic plants thrive in soft water containing a low general hardness (GH) and carbonate hardness (KH). Nutrients like nitrate and phosphate will make managing algae growth harder and could stimulate stringy algae to grow on the plants. It’s especially important to prevent algae growth when first starting a planted tank. We recommend a reverse osmosis system for planted tanks. You can either go with 100% RO water reconstituted for plants or blend RO with your tap water to create the right blend of minerals.
You’ll want strong, healthy plants for your aquarium. Many plants sold for aquariums look like house plants. That’s because they are house plants and cannot live under water. We carry Dennerle true aquatic plants. They’re grown under aquarium conditions so the plants are fully acclimated for submersed growth. Dennerle plants are free of snails and other unwanted hitchhikers that can get into your tank from lower-quality plants. One of the keys to success is to densely plant the tank. Adding a few plants won’t work. Plants outcompete algae for nutrients and release natural algae inhibitors. Without enough plants, the algae usually win the battle.
Plants need full spectrum light to drive photosynthesis. For most applications a LED fixture will provide bright full-spectrum lighting while minimizing energy costs. We have several Kessil pendants including the A80 Tuna Sun, A160WE Tuna Sun, and A360WE Tuna Sun that are ideal for planted aquariums. For a high-tech tank, you can push plant growth to the extreme with carbon dioxide injection and a wirelessly controllable light, like the EcoTech Marine Radion XR15W Pro or Aqua Illumination Prime HD Freshwater. For nano tanks, the Aquatic Life Reno, Lifeguard Aquatics Nano, Cobalt Aquatics Mini, or NemoLight AquaFresh are all attractive and under $100. You can use almost any properly sized LED or fluorescent fixture. Just remember that unlike corals, plants grow and look best in natural white light. Run the lights from 8 to 12 hours a day.
Aquatic plants need nutrients just like garden plants. Fish waste and fish food provide some nutrients like phosphate and nitrate but your plants are going to need trace elements to stay lush and colorful. Seachem’s Flourish liquid fertilizer will keep your plants colorful by replenishing essential trace elements and minerals plants need.
Carbon is an essential element used by all plants. Aquatic plants adsorb carbon from carbon dioxide dissolved in the water. With good lighting and nutrients, aquarium plants are almost always starved for carbon. Growth slow and algae can take over. When carbon dioxide is slowly injected into an aquarium, aquatic plants undergo explosive growth. Experience shows that adding CO2 transforms a mediocre planted aquarium into a thriving, lush Amazonian biotope. The Dennerle CO2 Complete Kit contains everything you need to get started with carbon dioxide fertilization.
Water Movement and Filtration
For filtration and water movement you can use a hang-on power filter like the Aqua Clear. If you like larger media baskets and filtration capacity, go with a canister filter. No matter which filter you use, the idea is move water without a lot of surface agitation. This will simply drive off the C02 plants need. If you need to create underwater flow, use a submersible flow pump like the Hydor Koralia. It will attach anywhere in the aquarium and is small enough to provide just the right amount of flow without “blasting” the plants.
Notice we put tropical fish last. That’s not because we don’t like freshwater species. It’s because once you provide what the plants need, the fish will be very happy. They’ll respond to the natural aquarium with vibrant colors, intricate patterns and beautiful fins. That’s because they’re in their ideal aquarium environment. Do the research and select plant-friendly fish.
We don’t like to compare plant tanks vs reef aquariums because they are two different styles of aquarium keeping. But it is true that both types of tanks provide unique challenges and rewards for the diligent aquarist. The cool thing is you can use any of the beautiful all-in-one reef aquarium systems for a planted tank. You don’t need a protein skimmer but you can use just about every other piece of hardware like LED lighting, dosing pumps, lighting controllers and more to maintain and customize the freshwater environment. In fact, many reef enthusiasts set up a planted tank to enjoy a natural freshwater tank alongside their reef aquarium.