File Fish behavior change

[Floyd-]

Ive had this file fish for only a couple of months and when he was new he wasnt afraid of anything and would swim right up to you during a water change and almost beg to be "pet". Now he darn near jumps out the tank when anything enters the tank (hands, tools) or even if someone walks by the tank. I put my mesh lid on the tank for the time but I thought id ask if anyone with a file fish has seen this sudden shift of behavior before.
For what its worth im not sure if he's just out grown this tank and he's panicking now. Its a 25g lagoon tank.

 

[Formulator]

Do you have a window near the tank? My glass gets a lot more glare and a few of my fish start fighting their reflection this time of year because of the way the sun hits my tank by a southern facing window. Kind of an oddball explanation but that’s what popped into my head as I’m sitting here watching one of my clowns defend her egg clutch against her own reflection

 

[KrisReef]

Do you have a cat?

 

[VintageReefer]

My filefish was the same way and then after about a year he started hiding behind rocks and I couldn’t figure it out. And I mean, always behind the rocks. Wouldn’t come out at all. He would eat food as it drifted back there.

I ended up adding a fish, a cardinal maybe? And next day and from then on he was back out in the open like normal.

I don’t know if it was related…but it certainly seemed related to me.

 

[Floyd-]

Do you have a window near the tank? My glass gets a lot more glare and a few of my fish start fighting their reflection this time of year because of the way the sun hits my tank by a southern facing window. Kind of an oddball explanation but that’s what popped into my head as I’m sitting here watching one of my clowns defend her egg clutch against her own reflection

I have a window near the tank but the blinds are always closed so there should not be a reflection. He does swim at the glass pane and acts like its a mirror though.

Do you have a cat?

Nope. Just fish.

My filefish was the same way and then after about a year he started hiding behind rocks and I couldn’t figure it out. And I mean, always behind the rocks. Wouldn’t come out at all. He would eat food as it drifted back there.

I ended up adding a fish, a cardinal maybe? And next day and from then on he was back out in the open like normal.

I don’t know if it was related…but it certainly seemed related to me.

I have a cardinal already.

 

[Formulator]

I would give it some time and see if he warms up again. Fish behavior can be a mystery sometimes but I don’t think you have anything to worry about other than not being able to enjoy your fish as much. I doubt he has outgrown the tank already, but I wouldn’t keep him in that tank for more than a year or so. You could try moving a rock. A change in scenery can often “reset” fish behavior.

 

[Floyd-]

I would give it some time and see if he warms up again. Fish behavior can be a mystery sometimes but I don’t think you have anything to worry about other than not being able to enjoy your fish as much. I doubt he has outgrown the tank already, but I wouldn’t keep him in that tank for more than a year or so. You could try moving a rock. A change in scenery can often “reset” fish behavior.

Ive shifted some smaller rocks in the hope to do just that and nothing has changed yet. I know he will get too large and will have to be rehomed but at the moment he's eating the aiptasia also.

 

[PharmrJohn]

My filefish was the same way and then after about a year he started hiding behind rocks and I couldn’t figure it out. And I mean, always behind the rocks. Wouldn’t come out at all. He would eat food as it drifted back there.

I ended up adding a fish, a cardinal maybe? And next day and from then on he was back out in the open like normal.

I don’t know if it was related…but it certainly seemed related to me.

I would agree. I'm not a big believer in coincidence.

 

[VintageReefer]

I saw OP said they already had a cardinal. For me I don’t believe it was the cardinal itself but rather that a new peaceful fish was added and out in the open and it invoked curiosity and also a feeling of safety and comfort. My new fish that I added happened to be a cardinal but I would guess there are others that could have the same effect.