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Why Does My Tropical Fish Appear To Eat The Surface Of The Water

It is often worrying when you see your tropical fish behaving in a different way than normal or than you would expect. Observing and watching your fish in their daily routine is always fascinating and the sign of a great fish keeper as it will be easier to spot any potential problems if they behave in a different way than they seem to have become accustomed to.

Something which is worth keeping an eye on is whether your fish are at the surface pointing upwards and appear to be eating the surface or gasping for air. In actual fact, they are normally doing just that – gasping for air or eating the surface.


The less concerning of the 2 is the eating the surface, I often find random fish on their own at the surface almost throwing themselves out of the water however this is simply down to the condensation covers/hood having food dried on to it so they are trying to jump out to get to the food. There is no real need for concern if this is the case, simply clean the dried on food and they will soon stop and find something else to occupy their time!

What is more cause for concern is if most/all of your fish are constantly at the surface, this is due to gasping for air which means the tank is overstocked or the water is not oxygenated enough or probably both. It is advisable to have a fish tank which is not overstocked to this level due to a power cut potentially causing issues with equipment not working although we have covered your options in our article about what to do with your fish tank in a power cut in another post.


Therefore the first thing and ultimate aim of what you will need to do if the fish are gasping for air at the surface is reduce the number of fish in your tank by rehoming them in a different tank and thinning out the numbers. In the short term I would strong advice increasing surface water movement either by positioning your filter outlet differently – discussed in more detail in our article about direction of filter outlets and/or adding a source of surface movement by means of bubbles. The best way of doing this is to add a pump and bubble-stone, you can see the best method of doing this in our post about how to set up bubbles in your fish tank.

The other method you can use is to add a power head to agitate the surface movement of the water in your aquarium. The key is to get more oxygen in to the water and the best method of doing this is to increase surface movement as the more the surface moves the more oxygen can get in to the aquarium water.

A high temperature can also reduce the amount of oxygen in the water so be sure to check the temperature is correct for your fish and not too high.