Why is my albino cory catfish always at the top surface of the water?

Question

He used to remain on the bottom like catfish usually do, but for a few weeks he's been constantly at the top swimming vertically with his mouth up at the surface. All the other fish are thriving and the tank is not at all overcrowded.

Answer 1

1) check ammonia, nitrite, and nitrate levels - he may be more sensitive to these than your other fish

2) check your water circulation at the bottom of the tank - depending on your filtration/aeration system, you may not be getting adequate water movement all the way to the bottom for good oxygen levels

3) along with #2, check your water temperature - if the temperature's too high, it will mean less dissolved oxygen in the water, but the fish will need more

4) check his gills to see if they are reddish, inflamed, covered with mucus, or have what look like threads coming out of them - he may have a gill parasite - you can treat this with an antiparasitic like Clout

Answer 2

To really be effective in answering this, I really need your water parameters - ammonia nitrite, nitrate, pH, and temperature. It could be a high nitrate problem.

The first thing in a situation like this is to suspect oxygen deprivation. You can buy a powerhead to circulate oxygen and create currents in the tank - a small submersible powerhead will run you about $25 and can have a filter attached to it to provide extra filtration. Change about 20% of your water and replace it with cooler water (a degree or two under tank water). Remove fish to quarantine tank (which can be a small 3 gallon tub as it will probably be temporary) filled with 2/3 tank water and 1/3 dechlorinated water and observe for 24 hours.

Second suspect is a parasite, or infection. Seeing as you said 'a few weeks' it could be something wrong with his gills - a fungus or parasite fouling them. You should remove the fish, place him in a quarantine tank. Try to see his gills with a magnifying glass for any problems. If you don't see any, aerate the quarantine tank with an airstone and leave him for 24 hours. If he still has gasping problems and refuses to eat, you can buy a broad spectrum anti-biotic at your local fish store and treat for infection of the gills.

Answer 3

it may desire to be countless issues, a million- he's lacking of oxegen- Gasping for air, 2- There isnt anuff food down the backside for him 3- Corys choose to be in packs of three or greater, 4- I propose you verify ph,ammonia, etc