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Will Algae Wafers Grow Algae? What You Need To Know!

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By Lindsey Stanton

spirulina algae wafer dissolving in tank

There are a lot of people who have been asking us whether or not algae wafers in your fish tank will cause algae to grow. It sounds like a very simple and straightforward question, but it is a little more complex than one might at first assume.

The answer to this question is both yes and no. Algae wafers will not grow algae, but they can cause algae to grow. Are you confused? Don’t worry because we are about to explain in detail.

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What Are Algae Wafers?

First things first, do you know what algae wafers are? Algae wafers are little pieces of fish food made out of algae. Yes, there are many types of fish out there who eat algae as a means of survival. Now, some fish eat algae as a primary source of food, or in other words, it is what they need in order to survive. That, or they just love eating algae.

There are also some other fish which just enjoy it. Either way, algae wafers are just like little fish food pellets or flakes, but made totally out of algae and meant to satisfy the needs of algae-eating fish. So far so good right? However, what does this have to do with our main question? Let us explain this algae wafer and algae growth problem.

kuhli loach
A Kuhli Loach eating an algae wafer. | Image Credit: Olga Chezhina, Shutterstock

Will Algae Wafers Grow Algae?

Ok, so the short answer to this question is no, algae wafers on their own do not grow algae. You see, algae wafers are made out of dried and treated algae. In other words, the algae contained in these wafers is not living, active, or growing anymore. It’s the same difference as if you were to compare live fish or fish meal made out of fish.

One of them is still alive and the other is not. Therefore, on their own, algae wafers will not cause algae to grow as there is nothing alive about them that has the ability to grow, bloom, or multiply. Algae wafers on their own do not grow algae. However, algae wafers indirectly causing algae to grow is a different question altogether.

Algae Wafers Have The Potential To Cause Algae Blooms

So, now we get to the yes part of the answer. While algae wafers themselves do not grow algae, they can in fact cause algae to grow and bloom, at least in certain circumstances. You see, algae feed on nitrates and nitrites, as well as other components in the water which result from the decaying process.

In other words, algae require the proper nutrients or water chemicals, with nitrites being one of these things, in order to grow. Algae also require a good deal of sunlight in order to grow. The problem with algae wafers is that they often sink down to the bottom of the tank and remain uneaten.

green algae aquarium
Image Credit: Vincenzo Palma, Shutterstock

Generally speaking, things like algae wafers and other fish foods, if they are not eaten in the first 5 to 7 minutes, will sink down to the bottom of the tank and they will stay there. This then results in the algae wafers beginning to decay.

This decay boosts the nitrogen cycle, and it causes nitrites and nitrates to release into the water. Therefore, decaying algae wafers turn into the food or the nutrients which live algae need to grow.

So, if there are already some remnants of live algae in the tank, there is enough sunlight, and that algae receive nutrients from the decaying algae wafers, then yes, it can cause algae to grow. However, this is also the case with pretty much any other foods that may remain in the tank and are allowed to decompose.

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The 4 Ways To Avoid This Issue

Ok, so now we have figured out that given the right conditions and circumstances, algae wafers can facilitate the growth and bloom of algae in your fish tank. However, you might now be wondering how this problem can be avoided.

Sometimes you might just have fish that require algae wafers for their diet. How do you stop the wafers from decomposing and causing an algae bloom? There are several things you can do here.

1. Do Not Overfeed Your Fish

First and foremost, the main reason why this problem tends to occur is due to a lot of uneaten algae wafers sitting at the bottom of the tank. Therefore, just do not feed your fish more than they can handle.

Feeding them too much will just result in the wafers sitting in the tank and decomposing. We cannot tell you exactly how much is too much, as this depends on the size and number of your fish, how much they eat, and how much they should eat in a given time period.

It is recommended that you research your specific fish so you do not end up overfeeding them.

feeding fish
Image Credit: Pixel-Shot, Shutterstock

2. Clean Out Old Algae Wafers Regularly

Ok, so sometimes no matter what you do, there will be algae wafers that remain uneaten. Now, if the wafers are only in there for a little while, say a couple of hours or even a full day, they might not yet begin to decompose and release nutrients that live algae needs for growth.

However, anything beyond that time, and the wafers will decompose. Therefore, bust out your little net, or whatever tool it is you use to clean your tank and scoop up debris, and remove those uneaten algae wafers before they can begin to decompose.

3. Make Sure You Have A Good Aquarium Filter

Algae, as we said before, feeds off of various elements in the water, such as nitrites which are created and released through the decay process. However, every fish tank should have a good filtration unit. The most important part of your fish tank filter in this sense is the biological media.

Biological media is designed to break down and remove the very substances which algae need for growth.

Therefore, even if you don’t clean out those wafers too often, the bio media in your filter should remove enough of these elements so that algae cannot grow or bloom.

large fish tank with plants and filter
Image Credit: M-Production, Shutterstock

4. Get An Aquarium UV Sterilizer

The other solution you can go with in order to combat this problem is to get a UV sterilizer. These are tools used to kill free-floating organisms in the water.

They help stop the proliferation of bacteria, viruses, and yes, algae, through the use of UV light. Now, beware that UV sterilizers cannot kill all forms of algae, but they do certainly help.

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All right, guys and girls, there we have it. So, algae wafers on their own are dead and do not grow algae. However, yes, when they are left in the tank, and the right conditions are present in the fish tank, then they can indirectly contribute to the growth of algae.

To help stop and control this issue, get a UV sterilizer, clean out the wafers regularly, make sure you have good biological filtration capacity, and just don’t overfeed your fish.

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Featured Image Credit: Olga Chezhina, Shutterstock

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