Why do fish incessantly swim up and down against glass?

[pitt420dude]

Does anybody else have this issue? Why do they do it? The fish that I have that do it the most are my Julii Cories, and my neons (although they are only a week old). Are they aquanting themselves with the tank? They are healthy and not hassled.

 

[wishbone]

So my theory is, it's the reflection on the glass. Have you seen finding nemo? Remeber "aunt flo"? I believe they think it's another fish and swim with it up and down like crazy. Many people have mentioned seeing this with reflective backgrounds as well. Regular glass with nothing behind it definitely can provide a reflection as well.

In addition, some fish are just known to do this. I've seen several descriptions of clown loaches that describe this behavior as normal.

 

[pitt420dude]

Hmm, that makes sense. I buy it, that explanation also fits nicely with the schooling fish predominantly doing it.

 

[mitche8359]

I like wishbone's idea, but I've always thought they did it for exercise.

 

[Meredith]

My corys do that on occasion, but my guppies do it all the time. The guppies seem like a playful group, it seems natural for them.

 

[RogerMcAllen]

Water flow hits the side, and then goes down/up. Many fish probably enjoy this current.

 

[QTOFFER]

Corys make frequent trtips to the surface to gulp air from which they extract oxygen in the gut.

Some of my tiger barbs swim up and down against the glass all the time - I think it's a combination of the reflections and the current that they seem to like swimming against.

I don't think it's anything to be concerned about - it's unlike the repetitive pacing observed in understimulated zoo animals.

 

[megladonsharky]

my clouds do it all the time ...

 

[Blucat]

ITs my molly's hobby and obsession

 

[BillHicks]

My Tiger Barbs do it all the time. At first I thought they were just getting used to the tank, but its been three weeks now and they still do it. I have cherry barbs in there but they don't swim up and down the front of the tank.

Actually I've noticed the Tiger Barbs do this when I come home, or I'm walking around the room. Sometimes when I've been sitting down for a while and not moving I look over and they've stopped doing this, they are just chilling out in the middle of the tank.

I can't figure out if they are chasing their own reflections (when I look at the tank from the side you can see the reflections of the barbs in the front glass perfectly) or if they are waiting to be fed. or they are just neurotic.

 

[Guest]

its all my fishies obsession some more than others

the cories its always fun watching them dash as fast as they can from top to bottom and my mollies swimmin up and down the wall but this is my theory, that the males do it more more often than females anyways my pleco has done that, he goes to the top and some big old air bubbles come outta no where which i notcied came out of his mouth so that means they are entertained, nothing bad

 

[Felf]

it's the latest fad since the macarena

 

[Guest]

the macerena is dead

it died right after it was born

*starts doint the macerena*

 

[cougaran]

My female guppy does it all the time, shes kinda lonely after the male croaked. I just found him stuck to the filter, so who the heck knows what happened to him.

 

[oldshell4481]

my oscars do it when they see me (they like food). other than that only my barbs do it, but they are also obsessed with bubbles, and the powerhead current.

 

[black udder]

It's all my pictus cat does. back and forth, up and down one side of the glass. All day, all night. Sometimes he'll mix it up with just doing circles against the glass in a particular spot.

He's done it as long as I've had him. Now and again he'll go take a rest, but then he's back to it. He'll stop to eat or chase somebody off, but otherwise, it's back to the routine.

I don't know how much current is where he's doing it, but there might be a reflection.

Either way - I don't think he's stressed - just seems to enjoy it.

 

[Fishyfanatic]

It appears that virtually EVERY fish does this when they are excited. my cichlids go nuts doing this.

 

[RoK]

My bala shark, rainbows, mollies, and nearly all my gouramis do that.

 

[Steven A]

I think It is there reflection when my fish have spawned etc .. (agressive behaviour) it is then when they start to do it. I think they think there reflection is and intrudor or something, as a matter of fact my mpuffers did it before they bred.

 

[Sanfranman]

I was concerned when I looked this up on forums and a lot of people suggested bad water or not enough oxygen or just unhappy fish. but then I realized that they do not generally do it in the front or the back of the tank, only the reflective sides. Further proof of this theory is when you shut the tank light off and shine a flashlight on then they will stop because they no longer see a reflection. And also I actually believe perhaps the tanks are made this way purposely so the fish will be getting a lot of exercise