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What to do if the AQUANEAT Aquarium Bio Sponge Filter keeps floating

The AQUANEAT Aquarium Bio Sponge Filter is designed to sink to the bottom of your fish tank. If you find that this product keeps floating in the water column instead, then you can take a look at this troubleshooting guide at Aquarium Blueprints to see how you can fix this issue.

1. For the first step, we recommend that you try squeezing the sponge as it may be filled with too much air.

Before doing so, you should take some water out of your fish tank and put it in a bucket or container. Afterwards, detach the airline from the AQUANEAT Sponge Filter and then put the filter in the aforementioned bucket and container.

Afterwards, squeeze the sponge in order to get air out of it. This process will also move any trapped debris from the filter; hence, you don’t want to do this inside your fish tank as the debris will end up going all over it.

Once you are done with removing the air out of the sponge, drop it into your aquarium again to see if will sink.

2. If the AQUANEAT Aquarium Bio Sponge Filter is still floating after you squeeze the air out of it, then its air flow may be too strong.

So, if possible, you can try reducing the flow rate. If your air pump does not offer this feature, then you can try adding an air control valve to the airline tubing connection.

3. You should also make sure that the airline tubing isn’t too short. If it is, then then it may be propping up the sponge filter.

4. Make sure you have the base of the AQUANEAT Aquarium Bio Sponge Filter attached to the bottom as it is design to weigh down the entire filter. Otherwise, the sponge may stay afloat in the water column.

So, if you removed the base previously, make sure you put it back on.

5. Furthermore, you can try weighing down the sponge by using a rock, wood or décor. The extra weight should help get the filter to stay sunk in the bottom of your fish tank.

6. If you have a smaller sized AQUANEAT Aquarium Bio Sponge Filter, then you may want to consider getting a bigger version as those are heavier.

When we used the “Up to 60 Gallons” version of this product in our two tanks, for instance, it would sink to the bottom immediately.