How to Fertilize Your Planted Tank the 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. If you live on well water, your water may contain lots of heavy metals and high nitrate levels, which is not great for drinking but might be really good at 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.

Aquarium companies release many types of fertilizers to cater to every case because everyone has different tap water, lighting, stocking and tank setups. For someone who is just starting with planted aquariums, this can make it difficult to navigate the many options available. We created an easy-to-use Easy Green fertilizer to help everyone. Our Easy Fertilizer line only consists of four, beginner-friendly products that are geared towards planted tank setups with low to medium lighting and no CO2 (carbon dioxide) 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 liquid fertilizer is all-in-one and provides all the nutrients your plants require. 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.)

We recommend testing the water every week because everyone has a different setup. Instead of testing for every nutrient, it is easier to do a 60 second test strip to determine how many drops or pumps of Easy Green are needed to achieve 25-50ppm 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. Use our water change flow chart to gradually lower the nitrate to 25 ppm or lower and then dose Easy Green as appropriate. 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 need some nutrients from the water columns, so you should provide both liquid and ground fertilizers for 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 are a combination of high-quality red and mineralized clays, as well as a mixture of topsoil and mineralized topsoil. They also contain essential nutrients like nitrates, phosphates, potassium, and iron. Insert a capsule as deep as possible in the substrate using your fingers or tweezers in a grid pattern spanning every 4-6 inches. If the heavy root feeders are not evenly spread out in the tank, then place the root tabs directly under the plants. 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. More information is available in the article on root tabs.

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. Easy Green may also have an excess of iron which could cause algae problems like hair algae.

Iron is an essential element that plants use to make chlorophyll. It is particularly important for plants with high growth rates and high levels of light. Therefore, if you notice the newest leaves on your plants are yellow or pale-looking from a lack of chlorophyll but the leaf veins are still dark-colored, then try dosing some Easy Iron. For more information on specific dosage guidelines, see our article about iron supplements.

4. Carbon easy

Fun fact: the liquid carbon products sold by aquarium companies – like Seachem Flourish Excel or API CO2 Booster – are not actually fertilizers and serve as poor substitutes for CO2 gas systems in 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, Easycarbon, is suitable for treating small amounts of algae. A pipette can be used to spot treat black beard algae or other difficult-to-remove alga.

Dosing Easy Carbon will not help if there is a lot of algae in the tank. The algae will grow back much faster than you can kill them. If the tank is heavily infested, it’s best to balance the lighting, fertilizer, CO2 and other factors. This will allow you to grow plants that can outcompete the algae. Liquid carbon is a good aid for treating the symptoms of an unbalanced tank but will not solve the root of the problem. Finally, don’t forget that liquid carbon can negatively affect more sensitive plants like mosses, vallisneria, anacharis, and Marimo moss balls so consider treating them a reduced amount. You can read more about liquid carbon in the article.

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. Easy Green is the most important product for hobbyists. Easy Root Tabs can be purchased if they already have roots. Easy Iron can be helpful for tanks that are high in light and have red plants. Easy Carbon can also be used to combat algae problems. Check out the full Easy Fertilizer line to boost the growth of your planted aquarium.