Adding aquarium plants to your fish tank has numerous benefits for the overall health of your tank, as well as benefits for the fish.
However, with plants comes different problem areas you could potentially face.
Aquarium plants may not be growing for a few different reasons which includes not having the correct substrate type, lack of nutrients in the tank such as iron, not enough or too much light, or too many water changes.
Keep reading to learn more about what could be causing your live aquarium plants not to grown and how to fix the problem!
Wrong Substrate Type
For non-planted tanks choosing a substrate is easy as you can place any substrate as long as it fits the needs of your fish.
For planted tanks however, any substrate will not do. This is because plants need nutrients not only to survive but to grow inside the tank.
Substrates such as gravel for example may be easy to clean, but will not hold nutrients that plants desperately need.
When choosing a substrate for a planted tank there are two main categories of a substrate. There are inert substrates as well as active substrates.
Inert substrates are basic sand and gravels which do not contain the nutrients that plants need.
When using an inert substrate additional fertilizers will be needed, such as root tablets or fertilizers that are water soluble, in order to feed plants the nutrients they need.
The benefit of inert substrates however is that they will not break down and will essentially last forever.
Inert substrates are also cheaper, however, additional fertilizers are required for any plants to survive.
Active substrates are what are full of nutrients that plants need to survive. This is the kind of substrate that is ideal for planted tanks.
However active substrates will require more effort as they can be more expensive as well as they can be stirred up easily.
As they are very easy to stir up into the tank it can be difficult to move plants around the tank when needed.
Active substrates are ideal for plants as they are full of plant nutrients to help the plant grow.
Also, they do not last forever and will need to be replaced every few years. Also, active substrates can cause a spike in ammonia levels in the tank.
Types of Planted Aquarium Substrate
All-in-One Substrates (Active Substrate):
All-in-one substrates are essentially a mix of many different types of substrates. They are prepacked with plenty of nutrients and additional fertilizers will not be needed.
The mix of different substrates allows nutrients to be held within the different grains.
All-in-one substrates are a popular choice for rapid plant growth in an aquarium. However, it is best if fish are not present in the tank as the substrate is added.
This is because the spike in nutrients from the substrate can cause a spike in ammonia. This ammonia spike may last for the first few days and can be deadly for your fish.
Also, the pH levels, as well as other levels of water parameters, may be affected during the first few days after adding a nutrient-packed substrate.
Fluorite (Inert Substrate):
Fluorite substrates are also made from several different materials. This includes the use of clay and volcanic soil.
These materials are used as they have a non-compacting way of settling in the tank. As well as being porous allow water flow as well as the collection of nutrients.
Because of this, organic matter, supplements, plant roots, and microorganisms can collect in the porous structure and create a living network right in the substrate.
It is recommended when using a fluorite substrate to add a few root tablets to add nutrients to the substrate.
Fluorite substrates will hold nutrients that it has absorbed and released them over time in a controlled manner.
The benefit of this is that supplements and nutrients are taken by the plants as food instead of wasting away in the water of the tank.
These wasted nutrients will end up filtered out of the water or broken down by bacteria in the water.
Lack of Iron in Tank
Another common reason for aquarium plants not growing is that they are simply not getting enough iron. Iron deficiencies not only present themselves by stunted plant growth.
Other signs of iron deficiency are leaves turning white or yellow and eventually leaves falling off the plant.
By testing the levels in your tank water you can quickly determine if low iron is the problem. The ideal level of iron for a planted tank is between 10 to 20 mg/l.
Fortunately if low iron is the cause of stunted plant growth it is an easy fix. Simply adding in an iron fertilizer should do the trick!
These iron fertilizers can either be added directly to the substrate, or there are liquids that can be poured right into the water.
Not Enough or Too Much Light
Lighting in a tank can play a big part in whether or not your plants will thrive. This is because different plants need different amounts of lighting.
It is very important to research plants prior to adding them to your tank in order to provide the appropriate amount of light.
In general, plants should have about eight hours of light per day in the aquarium. This is because the light is a key component in the photosynthesis process.
Photosynthesis is how the plant will consume food and grow. Even something as simple as the light not pointing toward the plant can affect its growth.
This means the light from outside of the aquarium may serve no purpose for your plant and the aquarium lighting will need to be adjusted for the plant to survive and grow.
The light of the aquarium should reach all parts of the tank. If there is a part of the plant that does not receive direct light and may likely die.
Typically a lot of aquarium hoods will have a fluorescent type of light. Basic fluorescent bulbs may not be the best for your plant.
Plants need a certain wavelength on the light spectrum in order to thrive and grow.
This means even if you have plenty of light in the tank, it may be the wrong kind of lighting.
Because of this, there are many different lighting options out there, with a little research you can choose the best one suited for your planted aquarium’s needs.
The most common lighting for planted aquariums include fluorescent light strips, compact fluorescent fixtures, and LED lights.
LED lights are more expensive, however, they are the most efficient type of lighting. LED lights are also the longest-lasting type of light.
Water Change Frequency
Even though water changes are a key to maintaining the cleanliness and water parameters of your tank, too many can cause a problem.
Water changes should be done less for your aquarium plants to thrive. This is because the plants in your tank receive the nutrients that are already in your tank.
All the nutrients that are needed for the plants are not there in tap water.
Frequently changing the water will cause the plants in your aquarium to not receive enough nutrients.