Why are my cory's going up and down the tank?

Question

All four were going up and down and cruising everywhere.

My water parameters are ammonia nitrite nitrate = 0, 0, and low nitrate

Is this something to look into or are they just playing or adjusting to the tank?

Answer 1

I'd say your corys could be any, some, or all of the ff:
1. Adjusting to their new environment.
2. Playing around for sheer fun.
3. Hungry, in search of left-over food and algae.
4. Chasing or getting chased by another fish.
5. Storing oxygen in their bellies. They have oxygen-storing capabilities to thrive in an oxygen depleted environment.

In any case, you shouldn't worry at all. Corys are hardy fish species who can store oxygen for a very long time, don't need an aerator, and can live on left-over scraps of food all their lives.

Answer 2

Hey, had to have a look at this question as I've had my corys for a over a year (so their not adjusting) and last month they started doing this strange tank dance, up and down, up and down. They are all still living so it's nothing to worry about, we put it down to mating and differences in the heat - Australia and coming into the warmer seasons. Dont have anything to worry about, they will go up and down the tank, swim around in cycles in the middle of the tank, it's a panic when they first start, but it settles down and they return to the bottom when they were hungry. Don't worry, and just enjoy them while their active!

Answer 3

While corys are usually bottom feeders, they don't always stay there. If they're new to the tank, they probably are adjusting and shouldn't be any cause for worry. I had a blind albino cory who seemed to like trying to find my angelfish and would race all over the tank until he swam into that one fish. Then he'd settle down on the bottom.

Answer 4

Corydoras always do that as they have the ability to use atmosphere air if the water is oxygen depleted.

Answer 5

Wher else can they go in a tank?

Answer 6

they're doing it for "fun".
corys like to swim everywhere.