Which Planted Tank Fertilizer is Right for You?

Which plant-based fertilizer is best for you?

Wondering how professional hobbyists and advanced hobbyists create stunning aquascapes that are bursting with plant life? It all boils down to three things that make aquatic plants happy.

– Good lighting. Substrate as required. – Nutrients like fertilizers.

Because the world of fertilizers is a confusing and complicated maze, many beginners will overlook this last piece. While dry fertilizers are highly affordable and customizable, everyone on the internet recommends them. However, they neglect to mention the steep learning curve and how easy it is for chemical balances to get out of control if you don’t know what you’re doing.

Aquatic Plants Actually Need Fertilizers

You want your plants not to survive but thrive. The building blocks that plants need to grow are just as important as the nutrients they require to survive.

– Macronutrients are nutrients that plants consume in large quantities, such as nitrogen, phosphorous, and potassium. – Micronutrients, which are nutrients that plants require in small amounts, include iron, boron and manganese.

Plants can grow differently if one or more of these compounds are missing. You can see the plant deficiency chart to see what happens when certain elements and minerals 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, I just bought my first few 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 originally designed for our in-store use, but we needed something more.

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. Reasonably priced because a little bit goes a long ways

Easy Green all-in-one liquid fertilizer

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

Easy Green has healthy levels of all three macronutrients for great growth. It is not recommended for tanks with high bioloads or 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. Having high levels of organics in the water produces nitrogen and phosphorus, which plants can consume. If not managed well, high bioloads may also cause high levels of ammonia which can be toxic to animals.

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. Easy Green is now available in Canada via 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. And that’s it – no other bottles to deal with.

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.

One bottle of this product will last approximately one year for a 55 gallon tank. 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 easy as pie.

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 most likely one of the available liquid fertilizers at your local pet store. The cheapest bottle should be enough.

API Leaf Zone

Intended For: low-tech planted tanks with really high bioloads

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

Ingredients: contains only potassium and iron

API assumes that your tank has high bioload and contains a lot of nitrogen, phosphorus and potassium. Leaf Zone also provides potassium. It also includes iron to aid in new leaf growth. But… what about all the micronutrients?

Cost: $6.50 for 8 oz bottle

You can’t beat the price but you get what your pay for.

Directions: 5 mL per 10 gallons per week

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

Summary: Although it won’t bring about super growth, it is better than nothing.

The Mix-and-Match Option: Seachem Flourish Series

Seachem Flourish fertilizer line

Intended For: any planted tank

The reason why Seachem has so many supplements is because everyone’s planted tank is unique – different bioloads, water hardness, low vs. high light, and so on. Seachem wants to give you the freedom to adjust the nutrients to suit your needs. Their fertilizers are not necessarily for beginners.

Ingredients completely depends. Most beginners should start with Flourish Comprehensive. This contains the majority of the minerals and elements you need to grow low-light plants. Seachem recommends that you add Flourish Trace to your diet on separate days in order to get enough micronutrients. If you’re still seeing plant deficiencies, Seachem has separated out key nutrients into different products so that you can individually buy the building blocks you require.

Price: $10-$70 or More

Flourish Comprehensive and Flourish Trace are about $10.50 each for a 16.9 oz bottle. They are low in nitrogen and phosphorus, just like API Leaf Zone. Flourish Nitrogen can be purchased for $10.50 and Flourish Phosphorus is available for $10.50. You could end up buying seven bottles.

Directions totally dependent

Not only are multiple bottles cumbersome to manage, but each one has very different amounts and treatment times. 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.

Bottom Line: Flourish Comprehensive contains a lot of the bare minimum nutrients needed for growing plants, but be prepared to buy additional supplements and to spend time fine-tuning your dosing schedule and amounts.

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

Final Tips on 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. Because every person’s preferences and setups are different, there is no one “best product” in the market. The key is to do your research, make a decision that works best for you, and 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!