How To Trim Aquarium Plants – Helpful Guide

It's important to keep your aquarium well maintained, a large part of that can be trimming your aquatic plants. Here is how to do it the right way.

Letting your plants grow too much will eat up space and will also not be good for the fish. You may think that trimming plants under water is going to be difficult, but from my own experience, as long as you know the proper procedure, it’s really not all that hard.

Some Things To Keep In Mind Before Trimming

There are a few things that you need to keep in mind before you begin trimming. Ignore these points and your trimming operation may not turn out to be as successful as you had hoped. (It’s important you have the right aquarium plant tools for the job too, we recommend the Apollo Aquarium Aquascaping Kit).

First of all, you will need the right tools for the job. Tools for trimming aquarium plants include shears, scissors, tweezers, razor blades, and more. Something that is recommended to have is some kind of long aquascaping tool so you don’t have to get your hands wet.

pruning aquarium plants

Another thing to keep in mind is the hydra affect. You know, like in Hercules when he cuts off one head of the beast, two grow back in the place of one. The same is true for many stemmed plants. This can be both good and bad for your planted tank.

In one sense it is bad because it will cause your stem plant to be much wider than before you trimmed it, plus it will require constant attention. Yet in another sense it is good because you can control where the plant gets wider and how you want it to grow.

The next important note to make is that the less plant life is in your planted tank, the less nutrients and carbon dioxide it will need. If you add the same amount of nutrients to your aquarium after trimming plants as before, your aquarium will have too many nutrients. Too many nutrients may can an extreme algae bloom and will also make your fish sick.

Finally, trimming an aquarium plant in a certain way depends on what the specific plant is. Some need to be cut in one way and some in other ways.

Below we have examples of the most common aquarium plants and how to trim them effectively and safely.

How To Trim Potted Plants

Trimming potted plants is not very difficult, however they do tend to grow fairly slow, and thus keeping them at the size you want may pose a bit of a challenge. Potted plants for your aquarium may include Amazon Swords, red tiger lily’s, crpyts, hair grass, and a few others. These plants don’t need to be trimmed very often and are fairly easy to maintain thanks to their slow growth.

Trimming potted aquatic plants isn’t too hard. Since they grow more in width than they do in size, they may become too thick. In that case all you need to do is use your trimming scissors to cut off the extra foliage at the base of the root. Not only should extra foliage be cut, but also dying or discolored leaves.

Dying leaves are a bad sign and in case it is an infection of sorts, cutting them away may save the rest of the plant. Also dying leaves may pollute the water with unwanted contaminants that will damage your aquarium’s ecosystem so they need to be removed as soon as possible. Keep in mind that these plants need to be cut at the root, not across the leaves themselves.

Cutting across the leaves doesn’t look nice and it may actually kill the plant over time. You should probably get a potted plant that will grow to the size you want and no more, as trimming them smaller can pose a challenge. When it comes to how to trim aquarium plants, these are perhaps the hardest to maintain.

Java Ferns And Anubias

Just like the moss that we will talk about later, these plants are extremely resilient and can take a whole lot of damage before there is any risk of them dying.

All you need to do to trim them down is to split the rhizome at the plant’s base, thus removing extra stems, leaves, and other foliage. Simply pull out the roots of the parts that you don’t want anymore, it’s as easy as that.

All you need is a sharp knife or razor blade to carefully cut apart the rhizome at the base. You can cut it into 2 or 3 parts, but preferably no more than that. If you want to keep the parts you cut off, you can actually plant them in other parts of the aquarium and they will continue to grow.

Also, if the plant is growing too high, such as ferns tend to do, you can also take an inch or two right off the top. Be careful not to cut away too much as that may result in weakened plant integrity.

How To Trim Stem Plants

Stem plants are the kind of aquarium plants that you will need to trim most often. This is simply because they tend to grow a lot faster than any other type of aquarium plant. You should keep in mind what you want your whole aquarium to look like because that will make trimming them easier in regards to what size you want them to be at.

Unlike potted plants, stem plants can be cut off the top instead of at the root. Cut anywhere from 1 to 3 inches off of the top of the stem in order to trim it. This will not affect the plant negatively and it will still continue to grow.

A general rule of thumb to be followed when trimming stems is to never cut away more than half of the stem. Cutting away more than half of the stem may irreparably damage the plant.

Stem plants are convenient in the sense that you can easily propagate them. You can take the parts of the stem that you cut off and place it in the substrate. In about an inch of substrate the cut stem of a plant will form its own root system and quickly grow into a full sized plant.

Stem plants require a fair amount of maintenance because they grow fairly quickly, so trimming them is a task that needs to be done quite often.

Trimming Moss

Aquarium moss is perhaps the easiest type of aquatic plant to trim and maintain. This is mostly because you can trim it any way you want and it won’t really affect the moss in a negative way.

Moss is very resilient so you can cut it off at the top to make it shorter and you can also cut it right at the roots to lessen the width.

Both ways of trimming work fine and depending on your needs you can do either or, or even both. Keep in mind that moss will grow slowly when there are many other plants around. On the other hand, the moss will grow quickly if the water content has a lot of nitrates in it.

You can actually take the pieces of moss that you cut off and tie them down with some thread or weigh them down with a coin in order to make them grow in other parts of the aquarium.

What Are The Best Aquatic Plant Scissors?

We’re just quickly going to mention two different tools which make trimming the plants in your aquarium a lot easier. In our opinion, if you have these tools, you really aren’t going to need anything else.

1. Fluval Flora Aquatic Plant Scissors

These are some great basic aquatic plant scissors that are sure to get the job done. They are very long, about 10 inches in length, and are also very skinny. This lets you trim even the deepest of plants with ease and ultimate precision.

They have a very convenient handle to hold on to, plus the material is rust proof so they won’t get water damaged. The specially designed blade ends also make it very easy to trim small plants without cutting away any important bits.

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2. Vktech 3 in 1 Aquatic Plant Tools

This is a fantastic set of aquarium trimming tools to get. If you have this set you won’t need any other tools because this constitutes a full trimming arsenal. This set includes a pair of straight tweezers and a pair of curved tweezers so you can easily grip and remove plant life from your aquarium.

This set also includes fine scissors with a slight curve in the front. The scissors are perfect for trimming both smaller and larger plants. They are precise, sharp, and long too. Each of the trimming tools in this set are slightly longer than 10 inches long, making them perfect for all of your aquarium trimming needs.

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There are many different kinds of aquarium plants and each of them has their own specific ways of being trimmed. If you need some suggestions on some starter tanks, we have covered a post here on 10 gallon aquariums.

As long as you have the proper tools and know what each plant needs and how they function, you really shouldn’t have a problem at all. Any questions about trimming your aquatic plants that you have, we would be glad to answer them!

Photo Credit: Eric Lewis (FlickrCC)

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