How to Fertilize your Plantted Tank in an EASY Way
We’re big proponents of getting live aquatic plants because of their natural beauty and ability to purify water, but a common question we get is, “Do I need to fertilize my aquarium plants?” From our experience, most people have to fertilize because fish waste does not provide the proper amounts of nitrate, potassium, phosphate, and other trace minerals that plants require to flourish. Another big factor is your local tap water. Well water can have high levels of heavy metals, high nitrates, and may not be safe to drink. However, it might be good for growing plants. In contrast, the tap water at our fish store near Seattle, Washington is so soft and stripped of nutrients that it is almost like RODI (reverse osmosis de-ionized) water – which is perfect for raising discus fish but insufficient for plants.
Because everyone’s tap water, lighting selection, plant stocking, and tank setups are so different, some aquarium companies try to compensate by releasing many different types of fertilizers to address every corner case. Unfortunately, such a vast offering can be very confusing for someone just getting started with planted aquariums, so we sought to create an all-in-one Easy Green fertilizer that would help as many people as possible. The Easy Fertilizer range consists only of four products, which are easy to use for beginners. They are designed for planted tanks with low to moderate lighting and no CO2 injection. With this goal in mind, the vast majority of our customers have great success with Aquarium Co-Op fertilizers because they contain all the right nutrient concentrations for most aquatic plants. A small percentage of users already have so many nutrients in their water that they don’t need as much help from fertilizers. Also, some hobbyists may want to set up high light planted tanks with pressurized CO2 that have specialized nutrient requirements to meet their objectives. To show you how easy the Aquarium Co-Op fertilizers are to use, let’s get started with a quick guide and figure out which of our fertilizers are right for you.
1. Easy Green
If you only get one fertilizer, Easy Green is the one you want. This all-in one liquid fertilizer gives you the right ratios of micronutrients to plants so you don’t have a lot of work. Like all of our fertilizers, Easy Green is completely safe to use with fish, shrimp, snails, and other invertebrates. Easy Green is available in two sizes. We have a dropper cap or a pump head that you can use to quickly dose. This makes it easier than other fertilizers. (See the product page for the dosage instructions we recommend starting with.)
Since everyone’s setup and plant stocking density are different, we suggest you test the water each week at first to really dial in the fertilizer dosage. Rather than test for every single nutrient, the easiest way is to use a 60-second test strip and figure out how many pumps or drops of Easy Green it takes to reach 25-50 ppm nitrate. As long as the nitrate comes predominantly from the fertilizer and not from fish waste, then your plants will thrive. If you have 75 ppm nitrate or more, don’t stop fertilizing because fish waste is missing a lot of key elements like potassium. You can use our water change chart to slowly lower the nitrate level to 25 ppm, then you can dose Easy Green as needed. The full article contains more information about proper dosing and nitrate for plants.
2. Easy Root Tabs
Easy Green is a liquid fertilizer that plants absorb from the water column. However, heavy root feeders like sword plants, cryptocoryne and bulb plants prefer to feed from the ground. (Heavy root feeders still take some nutrients from the water column, so providing both liquid and ground fertilizers gives you the best growth.) Many hobbyists like using nutrient-rich substrates such as organic dirt or expensive aquarium soil, but be aware that they can come with side effects like lowering the pH or leaching ammonia into the water (which is toxic to fish). If you are using a cheap, inert substrate like regular aquarium gravel or if your aquarium soil has run out of nutrients over time, just add Easy Root Tabs to fertilize the ground.
Easy Root Tabs contain a mix of mineralized topsoil, high-quality red clay, and many essential nutrients (like nitrate, phosphate, potassium, and iron). You can insert the capsule as far as you want in the substrate with your fingers or tweezers. The grid pattern should be every 4-6 inches. Place the root tabs under the plants if the heavy root feeders aren’t evenly distributed in the tank. For example, a small crypt may need one root tab, while a giant Aponogeton plant may need seven. We can use liquid fertilization to determine when to add more. But, for substrate fertilization we need to keep an eye on the heavy root feeders so that they don’t melt away or show other signs of nutrient deficiency. See the article on root tabs for more details.
3. Simple Iron
If you are trying red plants but not getting the bright scarlet hues you see on the internet, it is likely that you need high lighting. You may also want to add CO2 injection. Next, consider adding iron supplements. Easy Iron has its own bottle. This is because Easy Green’s formula already contains iron. Plus, if Easy Green contains too much iron, it could potentially lead to algae problems, such as hair algae.
Plants use iron to make chlorophyll. This is especially important for high-light plants and fast-growing plants. Easy Iron can be used to treat yellowing or pallor in the new leaves of plants that have not received enough chlorophyll. However, the veins may still appear dark-colored. For more information on specific dosage guidelines, see our article about iron supplements.
Fun fact: The liquid carbon products that aquarium companies sell – such as API CO2 Booster or Seachem Flourish Excel – are not fertilizers. They serve as poor replacements for CO2 gas systems within planted tanks. Instead, these products usually contain glutaraldehyde, which is a fish- and invertebrate-safe algaecide commonly used to inhibit algae growth. Our version of liquid carbon is called Easy Carbon, and if you have a little algae, it is good for treating the entire aquarium to help minimize algae over time. A pipette can be used to spot treat black beard algae or other difficult-to-remove alga.
Dosing Easy Carbon might not be enough if the whole tank is infested. The algae will grow back quicker than you can kill it. We recommend that you balance the lighting, fertilizer, as well as CO2 levels in your tank to ensure healthy plants. Although liquid carbon can be used to treat the symptoms of an imbalanced tank, it will not address the root cause of the problem. Remember that liquid carbon can cause more sensitive plants to be affected such as anacharis, vallisneria and Marimo, so it is worth limiting the amount you use. See the article on liquid carbon for more information.
Aquarium Co-Op aims to make fertilization simple. We want to help people who don’t know how to grow plants, or those who struggle to keep them alive. Most hobbyists need Easy Green, and then get Easy Root Tabs if they have rooted plants. Easy Iron is a good option for high-light tanks that have red plants. And if you have algae problems, try Easy Carbon. Check out the full Easy Fertilizer line to boost the growth of your planted aquarium.