Which Planted Tank Fertilizer Is Right for You?

Ever wonder how professionals and even advanced hobbyists make those gorgeous aquascapes 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

If you want your plants to really thrive and not just survive, the simple answer is yes. The building blocks that plants need to grow are just as important as the nutrients they require to survive.

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

Plants will grow differently if any of these substances are lacking. Check out this plant deficiency diagram that shows what happens when certain elements or 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 might be thinking “Uh, I just purchased my first few plants.” I don’t know if they are doing well or what nutrients they may be lacking. Where’s the easy button?” That’s where Aquarium Co-Op’s Easy Green all-in-one fertilizer comes in. We originally developed it for our own in-store use because we wanted something that was:

1. It is easy to use and does not require you to measure out tons of supplements. Higher in nutrient concentration and way more potent than what was available on the market 3. 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 is rich in all three macronutrients necessary for healthy growth. This fertilizer is not suitable for tanks with high bioloads, or 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 macronutrients (nitrogen and phosphorus) as well as the top six micronutrients are in greater concentrations to maximize 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 can also be purchased through Amazon.com Canada. Easy Iron can be used to boost iron levels in those with lots of red plants. If you need help fighting algae, consider adding Easy Carbon. There are no other bottles you need.

Easy Root Tabs can be used to attach to gravel, sand or any other inert substrate if you have plants that prefer to eat from their roots than the water column.

Easy Fertilizer Package

Directions 1 pump for every 10 gallons water once per week for low- to medium-light tanks; and double for high-light 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.

The bottom line: Easy Green is easy to use and great for making 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. This is the cheapest option and it should work.

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 only contains 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 throws in some iron because it helps with 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

This is a very diluted product, so you will go through the bottle quickly.

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

Seachem Flourish series – The Mix-and Match Option

Seachem Flourish fertilizer line

Intended for: Any planted tank

Seachem offers many supplements because every plant tank is different. This is due to bioloads, water hardness, low light vs. high lighting, etc. 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. 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.

Cost: $0 to $70 or More

Flourish Comprehensive is $10.50 and Flourish Trace is about $10.50 per 16.9 oz bottles. API Leaf Zone and Flourish Comprehensive are very low in the two main macronutrients, nitrogen and phosphorus. This is just in case your tank has a high bioload. 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 depends

Not only are multiple bottles cumbersome to manage, but each one has very different amounts and treatment times. Some bottles say “5ml per 60gallons per week”, while others say “2.5ml/40gallons twice a weekly but add more as needed.” In order to prevent novices from overdosing on fertilizer, the recommended nutrient levels are quite low.

Summary: Flourish Comprehensive provides a lot of the essential nutrients required for growing plants. However, you should be prepared to purchase additional supplements and spend some time fine-tuning how much and when to use them.

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. Because every person’s preferences and setups are different, there is no one “best product” in the market. 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!