Which planted tank fertilizer is right for you?

Wondering how professional hobbyists and advanced hobbyists create stunning aquascapes that are bursting with plant life? The three key ingredients that make aquatic plants happy are:

– Use good lighting. – Add nutrients as necessary.

This last piece is often overlooked by beginners because fertilizers seem like a complex and confusing world. Everyone on the internet is pushing for dry fertilizers because they’re cost-effective and highly customizable, but they fail to mention the extremely steep learning curve and how easily chemical balances can get out of whack if you don’t know what you’re doing.

Aquatic Plants Actually Need Fertilizers

If you want your plants to really thrive and not just survive, the simple answer is yes. Plants must also have the fundamental building blocks for growth, just as we humans need certain nutrients.

– Macronutrients are nutrients that plants consume in large quantities, such as nitrogen, phosphorous, and potassium. – Micronutrients can be nutrients that plants only require in small quantities, such as iron and boron.

Plants will grow differently if any of these substances are lacking. This plant deficiency diagram shows what happens when certain minerals or elements are missing.

(Source: Aquatic Plant Central)

To avoid these problems, hobbyists use fertilizers to make sure their plants always have access to all the nutrients they’ll need. Let’s take a look below at the most common and readily available fertilizers for your average tank.

The Easy Option: Aquarium Co-Op Easy Green

You may be thinking, “Uh-oh, I just bought my very first plants.” I have no idea if they’re doing well, much less what nutrients they might be missing. Where’s the easy button?” That’s where Aquarium Co-Op’s Easy Green all-in-one fertilizer comes in. It was initially developed for our own use in-store because we wanted something better.

1. Easy to use, without having to measure out a ton of different supplements 2. This product is much more potent and has a higher nutrient content than other products on the market. Because a little goes far, it is reasonably priced

Easy Green all-in-one liquid fertilizer

Intended For: aquariums that are at least moderately stocked with plants

Easy Green contains healthy amounts of all three macronutrients to get great growth, so it’s not intended for tanks with very high bioloads and only one plant. If you have an aquarium with normal bioloads and a bunch of plants that you want to look nice, this is the fertilizer for you. And yup, it’s fish and invertebrate safe.

Note: “High bioload” generally refers to aquariums with lots of animals, poop, and excess food floating around. A high level of organic matter in the water can lead to nitrogen and phosphorus that plants can eat. High bioloads can cause toxic ammonia if they are not properly managed.

Ingredients: all three micronutrients (nitrogen-phosphorus-potassium) and the top six macronutrients – in higher concentrations, for maximum effectiveness

Cost: $15 for 8 oz bottle

Easy Green is an all-in one fertilizer which covers most of your needs for plants. (Also, we now offer Easy Green in Canada through Amazon.com.) If you have lots of red plants, you can dose extra iron with Easy Iron. If you need help fighting algae, consider adding Easy Carbon. There are no other bottles you need.

If you have plants that prefer to feed from their roots rather than the water column (such as Cryptocoryne, sword plants, and bulb plants), then get a pack of Easy Root Tabs to stick into your gravel, sand, or other inert substrate.

Easy Fertilizer Package

Directions One pump per 10 gallons (or twice a week) for low to medium lighting tanks.

For a 55 gallon low light tank, that means one bottle will last you about a year. If your aquarium has medium to high light, then dose two to three times a week. Use test strips to measure the water in your aquarium and aim for 50ppm of Nitrates. It’s as simple as that.

Summary: Easy Green’s name means “Easy Green”, because it is simple to use and can make green leaves. Easy Green is a great choice for beginners looking for a bulletproof, comprehensive fertilizer.

API Leaf Zone is the Cheap Option

API Leaf Zone is likely to be among the liquid fertilizers available at your local pet shop. The cheapest bottle should be enough.

API Leaf Zone

Designed for: low tech planted tanks with high bioloads

Translation: your plants are fairly low maintenance and are currently living off fish waste and flakes in the tank.

Ingredients: has only potassium and iron

Because API assumes that you have a high-bioload tank with a ton of nitrogen and phosphorus, the only macronutrient you’re missing is potassium, which Leaf Zone provides. It also includes iron to aid in new leaf growth. But where are the other micronutrients, you ask?

Cost: $6.50 for 8 oz bottle

The price is not too bad, but you do get what you pay.

Directions: 5 mL per 10 gallons per week

That’s pretty diluted, so you’re going to run through the bottle pretty quickly.

Bottom Line: It won’t provide super growth for your plants, but it’s better than nothing.

The Mix-and-Match Option: Seachem Flourish Series

Seachem Flourish fertilizer line

Designed for: any plant tank

Seachem sells many supplements because each plant has its own unique bioload, water hardness, light intensity, and other factors. Seachem wants to give you the freedom to adjust the nutrients to suit your needs. Their fertilizers are not necessarily for beginners.

Ingredients it all depends. The majority of novices should start off with Flourish Comprehensive. It contains most elements and minerals that low-light plants need. Seachem then recommends adding Flourish Trace on separate days to ensure you have an ample amount of micronutrients. Seachem has made it possible to separate key nutrients into products, so you can purchase the building blocks that you need individually if you are still experiencing plant deficiencies.

Cost: $0 to $70 or More

Flourish Comprehensive and Flourish Trace are about $10.50 each for a 16.9 oz bottle. However, like API Leaf Zone, they’re very low on the two of the main macronutrients – nitrogen and phosphorus – just in case you have a high bioload tank. You can also spend $10.50 more on Flourish Nitrogen or $10.50 more on Flourish Phosphorus. By the time you have added all nutrients, you could be purchasing seven or more bottles.

Directions totally dependent

It is not only a hassle to have multiple bottles but also each bottle has different treatment frequencies and measurement amounts. Sometimes it says “5 ml per 60 gallons per week” and other times it’s “2.5 ml per 40 gallons twice a week but add more if needed.” Also, the nutrient concentrations are fairly low to keep beginners from overdosing, so more often than not, your plants will require much more fertilizer than the bottle recommends.

The bottom line: Flavorish Comprehensive has a lot more nutrients than you need to grow plants. But, be prepared for additional supplements and spending time fine-tuning the amount and dosing schedule.

For more details on the Seachem Flourish series, check out our video on How to Use Aquarium Fertilizers.

Final Tips for Aquatic Plant Fertilizers

No matter what nutrient sources you use (e.g., fish poop, root tabs, liquid or dry fertilizers, potting soil, CO2 injection), most likely they will help. There is no single “best product” on the market because everyone’s individual setups and preferences are so different. You need to do your research and make the right decision for yourself. Also, don’t forget to learn from your mistakes. Your aquarium is a living ecosystem that is constantly changing – water, number of fish, plant size – so have fun seeing nature in action and earning your aquatic green thumb!