Halfbeak broke beak

[Industrial]

So I got two wrestling half-beaks for my soon to be brackish tank and when I got home I realized that they are small enough that my purple spotted goby may try to eat them. I floated the one in a bag on the top to see what would happen and sure enough the goby tried to snap at him. But then I looked in the bag and the halfbeak broke off his lower beak as far back as his top beak in a blind dash.

I want to know how I could help it heal. Now he is in a 10 gallon tank and I am unsure about how many water changes how often. I am thinking 10% a day since halfbeaks don't like big differences. Also, what about stress coat or something? Is there anything I can add to the water to help him heal?

I don't expect the beak to grow back, but I want it to heal as good as possible.

I think these are the last fish smaller than the goby that I will be putting into the tank.

 

[Aqualung]

The beak actually can grow back. I had one break most of it's beak off once and it grew back eventually, although it was a bit abnormal looking. Just stay on top of water quality and it should heal just fine, additives are really not necessary.