A scum layer forms when there is too much protein in the aquarium. This buildup accumulates on the water's surface and is caused by overfeeding, overcrowding, dead rotting fish, or poor filtration due to bacterial death. By addressing these causes and changing the water, the scum layer disappears.
If you've been keeping an aquarium for a while, or are just starting out, you might notice a layer of scum forming on the water's surface. How do you remove this scum, and what causes it? That's what we'll explain in this blog post.
How do you remove a scum layer in an aquarium?
You can remove a layer of scum by suctioning the water surface, using a paper towel or placing an air stone.
A scum layer forms when proteins in the aquarium aren't broken down and float to the surface, creating a cloudy film. It's important to address the source of these proteins to prevent recurrence.
If the scum layer is caused by filtration problems, you simply need to wait for the filter to resolve the issue. If the scum layer is caused by food debris or dead fish, you can do the following:
- ✔ Proteins in the water
- ✔ Food waste
- ✔ Dead fish
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To remove the scum layer you can try the following methods:
- Drain the water surface using a plastic bottle, for example.
- Place an ink- and chemical-free paper towel on the surface of the water to absorb the scum.
- Place an air stone for more movement on the water surface.
- Feed less, but always ensure you maintain the minimum amount for each fish.
- Remove rotting food and/or purchase other fish food.
- Purchase a more powerful filter pump.
- Add floating plants to bring more balance to your aquarium.
Using good, strong aquarium plants is crucial for a healthy aquarium. The plants filter excess substances from the water, which helps keep your aquarium balanced and reduces fluctuations and algae problems.
A scum layer on a new aquarium, can that be harmful?
A layer of scum on a new aquarium is normal and not harmful if you follow the correct cycling process.
In newly started aquariums, a cloudy layer develops more quickly than in well-established tanks. This is because the filter still needs to be populated with beneficial bacteria that break down waste products like nitrite. We usually start the aquarium cycle with a planted tank, but without fish. During this cycle, we also add a small amount of food to the new tank. This encourages the bacteria to work more quickly. However, the result is a surplus of protein in the aquarium due to the (decomposing) food. This will accumulate on the surface of your aquarium and then slowly break down.
So, if you let your aquarium cycle for at least 2-4 weeks, you'll see the cloudy scum eventually diminish. Don't add any fish to the tank during this phase, as they could suffocate.
