How to Use Root Tabs for Explosive Plant Growth

Planting the aquarium with the desired plant is not a dream anymore. Lots of useful products in the market make it possible for newcomers to own a planted aquarium. 

Root tabs are the cheapest way to fertilize your plant while providing the essential nutrients. Because of its low price & easy to use, it is prevalent among the fishkeepers.

However, you need to know how to use root tabs in the right way. Here, in this article, I’ll describe everything about root tabs & will share some invaluable tips for effective application from my personal experience. 

Root or Water Column Fertilization?

There are two ways of fertilization in a planted aquarium. One is water column dosing (direct dosing of fertilizer in the water in a liquid form). The other one is root fertilization (using substrate-based fertilizer, usually in solid form). Most plants can absorb nutrients in either way.

Liquid column fertilization is hugely beneficial when your plant’s root system isn’t well developed. Since the water column is open to all, aggressive plants will obviously take what they need first. So, regular & consistent dosing is required, and the advantage is you can precisely measure the fertilizer amount.

Root Vs Water Column Fertilization

Root fertilization is using a substrate-based slow-release fertilizer, which dissolves gradually over a few months. Even though you can’t measure as precise as water column dosing; however, you can target specific plants by placing the tabs near their roots.

Nutrient sucking abilities vary according to the plant types. For example, if you have all sorts of aquarium plants like floating plants, stem plants, carpeting plants, etc., keeping necessary nutrients in both substrates or liquid columns will benefit the plant growth.

What Are Root Tabs?

Root tabs are the nutrients for plants in tablet or capsule form. It’s similar to the vitamin tablets we take to ensure we do not suffer from nutrient deficiency. Likewise, root tabs provide essential nutrients to the plant, a must-have for flourishing plants with roots.

What Are the Ingredients of Root Tabs?

Root tabs are made of top mineralized soil or red clay, containing essential macronutrients for plants, including iron, carbon & phosphate. Some root tabs also contain micronutrients. It is soluble in water and usually doesn’t harm fishes if no toxic element is used during the preparation.

What Are the Ingredients of Root Tabs

Which Aquarium Plants Do Need Root Tabs?

Root tabs are not necessary for all types of plants. Plant’s nutrition absorbing ways & abilities vary according to the classes. For example, some can suck nutrients directly from the water, whereas others want substrates, like soil, sand, or clay pebbles, to absorb.

Root tabs are usually required for plants that take nutrients from substrates. For example, sword plants, carpeting plants, a few tuber & bulb plants, and some stem plants grow better with root tabs. On the other hand, floating plants usually don’t need root tabs rather liquid fertilizer

How To Use Root Tabs (Few Essential Tips)

Using the root tab is pretty straightforward. Before doing that, keep in mind a few simple tips to better use those nutrient-rich tablets. Check the tips & tricks and follow the step-by-step procedure described below.

How to Use Root Tabs Tips

Tips-1: Use the Best and Safe Root Tabs

There are many variations of root tabs in the market. However, before using it in your aquarium, be careful to check it’s safe for aquarium use.

If it’s not safe for your lovely fish, you may find a green aquarium with no live fish available. Root tabs containing a high copper amount are not suitable because the copper can be harmful to fish.

Use the Best & Safe Root Tabs

Personally, I have used API root tabs, ThriveCaps, and Seachem root tabs, and they are not only the best among all the brands but, most importantly, the copper content is very low.

Tips-2: How Many Root Tabs to Use

Now the next step is to know the exact quantity. Every chemical in the world can either be harmful or helpful, depending on the right dose. Even water can be dangerous for the human body if it exceeds the maximum limit.

Similarly, for aquarium plants, root tabs are supposed to help plant growth; however, they can be deadly if you overuse them. You need to find the perfect amount according to your aquarium size & amounts of plants you have.

How Many Root Tabs to Use

The best practice is to start from a small amount, observe your plant’s growth, and adjust accordingly. However, if I imagine you have plants all through the substrates, use one tab every 4-6 inches of substrates.

For larger plants or heavy root feeders like Amazon Sword, you may need to make a circle around the plants’ roots for better growth.

Tips-3: Target the Roots (Go Deep Enough)

If you have 2-3 inches of substrate covering, I recommend penetrating at least half of the length and putting them as much closer as possible to the plant roots.

Since you’ve kept closer to the roots, they will be able to absorb the nutrients much better than remaining apart. Please do not break it down or remove the fertilizer from the capsule; otherwise, it’ll dissolve in the water more rapidly.

How far to push the root tab

When you start adding root tabs in the aquarium, you may have some sort of side effects. Few people mentioned they’ve had issues like fish dying, sudden ammonia spikes in the tank.

That’s because you are adding food for the plants in the substrates; sometimes, the food can push up through the substrates into the water column.

One of the keys here is to make sure your tabs are deep enough into the substrates.

I’m not suggesting you go too deep because the plant’s root may not be so deep, but yet deep enough that it doesn’t leach into the water column.

Tips-4: Keep Closest to The Hungriest Plants

There are visible signs on the leaves of the plants whether they are getting proper nutrients or not. You may check the plant’s deficiency chart for a better understanding.

Where to use root tab first

Check for the ones that are deprived of nutrients. Then, try to put tabs closer to that one. Gradually you’ll observe the sick plant is getting healthier.

Tips-5: Replace Every 3-4 Months

Depending on the plant growth, you need to reinject the tabs from time to time irrespective of substrates, nutrient-rich or inert.

Using inert substrates like sand and gravel will require frequent addition to continually keep the nutrient base in the ground because they don’t contain any nutrients of their own.

When to replace root tab

It also varies on brands; API root tabs need to replenish once a month. Conversely, Seachem tabs require once in three months. So a slight change may require in the redosing time frame based on your plant’s growth. 

Tips-6: Use A Tweezer (You Can Use Your Hand Also)

Since it is soluble in water, you need to put it in the tank quickly but correctly. If you don’t want to put your hands in the water, use a tweezer to hold the tablets.

You can make a mark on the tweezer how far you want to push the tab. Bring the tweezer inside with the tabs, find the preferred location and push that through the substrates up to the mark on the tweezer.

Best Root tabs for Planted tank

There are so many root tabs available in the market; among them, I’ll talk about the three best root tabs in the market.

Which aquarium root tabs you should buy depends on several factors, including types of substrates, types & quantity of plants in your aquarium. Other criteria are the types of aquatic critters you own in the tank.

Some tabs are safe for use in fish but harmful for invertebrates. Therefore, a careful selection of root tabs is mandatory for getting the optimum results. So, check out the review and choose according to your tank requirements.

Seachem Flourish Root Tabs

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Seachem Flourish root tab is one of the best root tabs in the market. It’s beginner-friendly & contains essential nutrients, including trace elements, amino acids & vitamins. 

It is safe for fish, shrimp & invertebrates since it contains only a too small amount of copper. You can use this root tab as a sole source of nutrients for undemanding plants using inert substrates. 

You can also use it for high-demanding plants. However, in that case, I recommend applying nutrient-rich substrate instead of inerts because it contains slightly lower nitrogen levels. 

How to use Seachem Flourish: Bury the tabs halfway through substrates 4-6 inches apart and replace them every 3-4 months. Seachem tabs won’t disturb the pH of your tank but may be slightly acidic in nature. 

Thrive Root Capsule Fertilizer

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ThriveCaps are nutrient-rich capsules that contain macro and micronutrients and other vital minerals for better plant growth. Moreover, it is entirely safe for aquarium use because it carries only 0.0001% of copper. 

ThriveCaps are prepared from mineralized topsoil and iron-rich clay with the proper blend of dry Thrive mix. It is equally suitable for low and heavily planted fish tanks. 

How to use ThriveCaps: You need to push ThriveCaps as deep as you can under the substrates because it tends to float. I recommend using ThriveCpas with dense or heavy substrates. 

Suppose it pushes out through the substrate & comes into contact with the water. In that case, the capsule will dissolve readily, which may create an ammonia spike in the tank. 

Place the caps near the plant’s root or space out around the tank every 5-6 inches in a grid pattern. Replace them every 3-4 months or as per the plant’s requirements. 

API Root Tabs

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Another best root tab for planted tanks is the API root tab, which is also vastly popular among fish keepers. API root tabs are formulated to develop strong plant roots, containing all the critical nutrients alongside iron, potassium, and carbon. 

API tabs contain a higher amount of nitrogen and iron than Seachem Flourish. Although it doesn’t carry any micronutrients, it’s good enough to get flourishing plant growth.

API root tab is safe for tropical fishes and suitable for both low-tech and heavily planted aquariums. 

It dissolves a lot quicker when exposed to water compared to other tabs. Unless you bury it correctly, it can melt into the water column, which can cause cloudy water, algal problems, or ammonia spikes. 

How to use API root tabs: Push the tablets midway to the substrates and add one tablet per 30 square inches of the surface. It would help if you replenished once a month to keep the nutrient in the substrates.

DIY Root Tabs

You can easily make your own cheap but effective root tabs by yourself. It’s super simple.

Let’s talk about the ingredients you need to create root tabs. The first thing you have to buy is ‘size 00’ gelatin capsules.

You need gelatin capsules because once you put them into the water and drown it in the substrates, the actual capsule itself will dissolve. It will just leave the fertilizer down under the substrates.

So, what do you require to fill up the gel cap? First, you will need Aquarium-safe fertilizer grains.

I recommend you to buy the Osmocote Plus – easily; you’ll find it online or at your local pet stores. It contains a perfect mix of macro & micronutrients.

What I like most about this Osmocote Plus is its slow release capacity. Granules can be active for six months, ensuring long time nutrition for the plants.

Each granule has a resin coating that controls the release of nutrients. It is perfect to utilize in a heavily planted high-tech aquarium.

Although it contains a slightly higher amount of copper than others, it’s 0.05% by weight; however, this concentration isn’t enough to harm fish or shrimp.

Now, it’s time to make the tabs. Take gelatin capsules, pull that apart & fill the longer side with Osmocote balls.

Then put on the shorter side; once you close it, it will be locked tight. It’s only a matter of 2 seconds to make one capsule.

Best Root Tabs For Fish Tank (My Choice)

According to the practical use of many root tabs in my planted aquarium, I found Seachem tabs are the best.

It lasts longer and includes micronutrients along with essential macronutrients. I also experienced better plant growth with this Seachem product.

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How many root tabs for 10 gallon

Although it varies according to the brand and types of plants you have, a thumb rule is to use 5-6 tabs in a 10-gallon aquarium.

Are root tabs safe for fish?

Yes, absolutely; make sure the copper amount it contains isn’t too high to endanger your fish. Moreover, follow the tips mentioned above on how to use root tabs correctly.

How long does it take for root tabs to work?

It doesn’t take long; as soon as it releases the fertilizer in the substrate, your plant can take the nutrients. Within a week, you will notice a significant change in plant growth.

It lasts three-four months, depending on the brand, how heavily your aquarium is planted, and the types of plants you have.

Wrapping Up

Root tabs are incredibly beneficial for establishing & maintaining a planted aquarium.  However, make sure you know how to use root tabs properly in your aquarium. If you follow the tips outlined in this article, hopefully, you won’t get any difficulties. 

Sujit Modak

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