I have 2 bengal loaches & 2 golden zebra loaches that after the last tank clean a good few days ago have been swimming up and down the side of the tank (where I think they'd see their own reflection) virtually non stop ever since! They do not move from this spot at feeding time (although I'm sure they do once lights are out).

It is like a courtship dance in a way and sometimes the corydoras join in too, and on a few occasions the clown loaches!

Does anyone know why they are doing this?

Cheers.

Im not sure in regards to your question but my clown loaches did this the other day for a couple of days when we changed their enviroment around from a ship to driftwood, and a nice tank clean, I was a bit worried but now they seem to be ok and not doing it anymore, I read up on clown loach breeding and Im pretty sure that what they were doing wasnt really part of it, unfortunately! lol

I don't think fish would see their own reflection inside the tank. Fish commonly follow people around the outside of the tank.

I think the reflections we see are an artefact of us looking into the tank, rather than what the fish is able to see.

Then again... if you think about it like your room.... if the outside is lighter than the inside you can see out through the windows. If the inside is brighter than the outside it just looks dark outside and you may get reflections on the window....

Anyone?

maybe it is just the change in environment rather than dancing to their own reflections! we've been changing the rocks around and put in a few more as well so maybe thats why they are continuing to do it, although they are not doing it at this very moment in time! they're not doing any harm, i just wanted to understand why!

its light inside my house right now, dark outside, if i look out the window i see my reflection. it would be a reasonably similar situation for my fish as the light into the tank is very bright and there wouldn't be a lot of light outside the tank in the corner they dance in, its possible they can see their reflection i guess! they just seem "enchanted" like a cobra and a snake charmer! i don't think they're trying to breed, that would be very cool though!

since the big cleanup (they all had to come out as the undergravel filter had stopped working) also my port hoplo catfish haven't been themselves, they are usually first in at dinner time eating everything they can find. the last 2 feeds they've stayed asleep and more or less missed it, so unlike them. they are out and about at the moment as if hunting for food, next feed isn't until tomorrow though

My Neon's and Golden Barbs to a lesser extent do the same thing. The Neon's are at it regularly and always in the same spot, the side wall of the tank in the left front corner.

It doesn't matter if I've just changed the tank or haven't done anything for a week.

my loaches stopped doing their little "dance" a few days after my last post, i think for them it was maybe something to do with the water change and change in set up. some of the other fish do it from time to time too but its ok they're not causing any harm! maybe it is something do with seeing their reflection!