Aggressive chalk goby, is this normal behaviour?

An_Enemy · May 12, 2018

We've had our goby for three weeks and introduced a clownfish and clown goby a week ago. Since the new fish came in, the chalk goby has been very territorial and does chases the others if they swim to the bottom of the tank, even nipping them if he gets the chance. Today he was chasing our clown around the tank after he tried to eat a pellet and we've noticed some of our clown goby has a little of her tail missing, which we suspect is at the hands (or fins) of the chalk goby. I doubt it's the clown since he and the clown goby seem to have bonded and stick together in the corner of the tank. We're worried since the clown seems to be getting stressed and hasn't been eating?

Does this seem like normal behaviour for a chalk goby? Does anyone have any experience with it and if so, how did you handle the aggression? He's a fun little guy to watch, but he's not mixing well with his tank mates.

Carterfish · May 12, 2018

Maybe change up the tank to provide different hiding spots and destroy their previous “territories” Or you can put him in acclimation box or remove him temporarily as a “time out”. But I️t could just be fairly normal behavior. I don’t know a lot about them but in my tank when a fish steals food from my trigger they get chased around the tank. Never biting though. How did you acclimate the new fish?

An_Enemy · May 12, 2018

Carterfish said:
Maybe change up the tank to provide different hiding spots and destroy their previous “territories” Or you can put him in acclimation box or remove him temporarily as a “time out”. But I️t could just be fairly normal behavior. I don’t know a lot about them but in my tank when a fish steals food from my trigger they get chased around the tank. Never biting though. How did you acclimate the new fish?

Thanks for the reply and advice!

We floated the fish in the bag and dripped in tank water. No quarantine since they're all from the same source and we have very few fish. I'll try rearranging the tank tomorrow and see if the behaviour ends.

Carterfish · May 12, 2018

Yea I believe that might do it. The chalk goby simply is trying to be dominant and protect his territory.

An_Enemy · May 13, 2018

Ok, the goby attacked the clownfish today and made a large tear right down the dorsal fin. We've rearranged the tank now, so hopefully this will make the goby a little less territorial.