Aquarium Plants

Why do Aquarium Plants Turn into Mush? Find out Now!

6 min read

Getting live plants for your aquarium is one of the best decisions you can make. There’s nothing like a beautiful backdrop of aquatic plant life against which your fish swims. The way the leaves dance in the water will be mesmerizing to watch.

And it is not simply about aesthetics, no. There are real benefits to having plants in your aquarium. For instance, plants provide oxygen for your tank – a vital component. 

Also, plants can help with nitrogen cycling by absorbing ammonia, nitrite, and nitrate, which are toxic to fish.

With all these benefits, having plants in your aquarium seems like a no-brainer. However, there are certain challenges to growing them. One of them is the melting of aquarium plants.

So, why do aquarium plants turn into mush? We’ll answer that question in this article and also look at how to prevent aquarium plants from turning into mush.

Let’s get started.

Why do Aquarium Plants Turn into Mush?

This is a scenario dreaded by aquarium owners – your beautiful aquarium plant loses its color and becomes translucent. Or it may turn brown. They are often sticky or slimy to the touch.

There are many reasons why aquarium plants turn into mush; we’ll look at each of them in the following and how you can prevent it from happening. 

Lack of Nutrients

Plants – like all living things – need nutrients to sustain themselves. They require a multitude of nutrients, such as nitrogen, sulphur, potassium, phosphorus, and magnesium.

Without these nutrients, your plant will suffer, and may eventually die. Parts of your aquatic plant dying or turning into mush is an indicator of poor nutrients.

For example, if there isn’t enough phosphorous, plants grow small and develop dark brown spots. And if there’s potassium deficiency, the leaves will have brown circular patches. Plants such as Anubias and Java fern require a lot of potassium, so they are likely to develop this deficiency. 

How to Fix…

Simply adding some fertilizers should fix the issue. While it is true that fish food and fish feces provide some of the nutrients, they may not be enough sometimes. And certain conditions, like the growth of excess algae, can siphon nutrients away from your plants.

Physical Damage

Sometimes, the simplest explanation is often the correct one. In this case, the plants turn to mush because they have been damaged. Inevitably, the damaged parts will die off. This isn’t necessarily a coup de grace for your plant unless it is the stem or root that is damaged.

You can damage your plant while you are planting it. Even your fish could nibble away at your plant, causing damage. 

How to Fix…

Prevention is the best strategy here. Be very careful when you are placing the plants. If you suspect you have damaged the root or stem, it is better to get a new one to plant – you wouldn’t want to waste your efforts on a plant that is doomed to die. 

In order to stop your fish from eating your plants, you can choose plants that your fish don’t have an appetite for. For example, Java fern is shunned by most fish. 

Insufficient Light

As you probably know, light is the form of energy that sustains plant life through the process known as photosynthesis. Without sufficient light, your plant will starve of energy and the leaves will turn brown. 

That doesn’t mean you should bathe your aquatic plants with a powerful beam either; too much light can make your plant wilt. Moreover, not all light is good: your aquarium should be kept away from sunlight since it can promote the growth of algae. 

If you ever wondered why do aquarium plants turn brown, now you know light is behind it. 

How to Fix…

Install proper lighting for your aquarium: get either an LED or a fluorescent lamp (preferably the former). Avoid incandescent lamps as their light doesn’t penetrate the water well (Also, your electric bill will soar). Make sure your plants get 10-12 hours of light every day. 

Transition Stress

Ever noticed that the aquarium plants are likely to turn into mush some time after they have been planted? There is a good reason for it.

Right after transition is a vulnerable time for your plant. It is essentially plucked from its original environment and planted in an alien one; it will struggle for a while to adapt to the new environment if it ever does. 

Adding to the woes, commercially, plants are grown emersed (parts of the plant are above the water line). This is because it is easier to grow and transport.

However, when you plant it, it’s going to be submersed. The plant needs to adapt from its emersed environment to the submersed one, which means it has less access to oxygen, carbon dioxide, and light, while also having to deal with algae.

How to Fix…

If you are buying emersed plants, you will have no choice but to put your plant through this ordeal. However, your plant will most likely survive, as long as you maintain conditions conducive to plant life, such as plenty of CO2, proper lighting, and sufficient nutrients. Choose healthy plants to increase the chances of surviving the transition.

Alternatively, you can search for vendors that provide submersed plants. If you can’t find one, you can ask for help from your fellow aquarium keepers – they’d be more than happy to share some of their excess growth. 

Lack of Carbon Dioxide or Oxygen

Carbon dioxide is a vital ingredient for plant growth. Without it, plants will turn brown and wilt. Did you know that 50% of a plant’s dry mass is attributed to carbon? So you can guess how important it is. The CO2 levels in your tank should be within the range of 20 to 30 mg/l.

And don’t forget, your plants need oxygen too, like all living things. It is true that they can produce their own oxygen during photosynthesis, but other times they need to absorb it from the environment. 

How to Fix…

There are natural sources of CO2 in your aquarium, such as your fish and decomposing organic waste. But sometimes they may not be enough, especially if you have a lot of plant life. In that case, CO2 injection is a good idea.

Also, having a good gas exchange in your tank will make sure that there are sufficient levels of oxygen and carbon dioxide in your water. There must also be good circulation in your tank.

You can try getting plants that require less CO2, such as Anubias, Java fern, and Crypst. You may also want to reduce the amount of light available to plants – more light equals more photosynthesis, which means more CO2 consumption.  

Improper Nitrogen Cycling

You have probably heard of the importance of nitrogen cycling for your aquarium multiple times already. Ammonia is a compound toxic to fish that can build up in your tank. Too much ammonia is harmful to plants too.

Usually, your biofilter will contain nitrifying bacteria that convert ammonia to nitrite, and then to nitrate (which is actually a plant fertilizer). However, it takes time for this process to find equilibrium. Until then the levels of ammonia, nitrite, and nitrate will be fluctuating. 

How to Fix…

Do not rush to introduce the flora and fauna as soon as you set up your aquarium. The biofilter will take about 3-8 weeks to cycle properly. You need to add some ammonia to your tank to start the process. You also need to seed your biofilter by adding nitrifying bacteria. 

Some Final Thoughts…

Now you know the answer to the question “Why do aquarium plants turn into mush?”. Aquatic plants aren’t any different from their terrestrial counterparts; they require sufficient nutrients, light, CO2, and oxygen to survive. Also, transitioning is a vulnerable time for your plant, so you need to be extra careful. 

As long as you provide your aquatic plants with everything they need and avoid shocks to their system, they will thrive and flourish, adding an element of natural beauty to your aquarium. Thanks for reading!


Written by:

Pet Aquariums

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