Kole Tang attacking his reflection

jasonrusso · Oct 30, 2016

I got a Kole Tang about 2 months ago. Besides from a couple misunderstandings with my foxface, he has been a good resident. This week, in the evening, I noticed him tail slapping the glass over and over again. I realized that he is attacking his reflection. If I turn the room lights on he stops. If I put my hand on the glass he stops.

I think it just started recently because now the room is dark at night, while before there was sunlight in the room for longer. That's why it I turn the light on, he can't see the reflection as well.

What should I do? Will he eventually outgrow this? He has a couple marks on his nose, but I'm not sure if it's from that.

mchnbuilt · Oct 30, 2016

I'm having a similar problem with my Tomini all of a sudden as well. Is your kole slightly more aggressive with other fish as well.

Bdog4u2 · Oct 30, 2016

It's normal for fish to go after their reflection. When I set up a fish trap I don't use food I put a mirror inside the trap the last time I did this i caught every fish in my old tank in less than 5 mins and all at the same time. But if your tang is hurting himself he might be a little aggressive

jasonrusso · Oct 31, 2016

mchnbuilt said:
I'm having a similar problem with my Tomini all of a sudden as well. Is your kole slightly more aggressive with other fish as well.

I've seen him and my foxface have a few stand offs.

eatbreakfast · Oct 31, 2016

It's definitely normal behavior. I wouldn't be too worried about it.

jasonrusso · Oct 31, 2016

Will it stop eventually?

eatbreakfast · Oct 31, 2016

jasonrusso said:
Will it stop eventually?

Most likely not. It may diminish in intensity, but they don't recognize themselves in a reflection, so any time they see their reflection, they will think that there is an intruder in their territory.

jasonrusso · Oct 31, 2016

He's not a happy camper at all, lol

mchnbuilt · Oct 31, 2016

jasonrusso said:
I've seen him and my foxface have a few stand offs.

Yeah he nips at my foxface's spines every now and then. Just started going after the clowns.

jasonrusso · Oct 31, 2016

My foxface is very timid and they both try to hide in the same cave. I feel bad for the foxface because he turns black (stressed), but 3 minutes later he's normal color and swimming again. I bought another algae clip for the other side of the tank just in case it was food aggression. I was away for 3 days last weekend and the algae ran out. I'm not sure if that's when it started.

I'll have to monitor the situation.