Bala sharks getting battered

hmmm.. 240 liters equals out to 63 US gallons. That is a pretty small tank for a fish that will out grow them. I think this tank might be a bit over crowded here. I wouldnt think to keep fish this size in this size of tank.
 
Thats a pretty nasty looking problem, whatever it is. I don't think that is from hitting anything in the tank, but I would keep an eye on them. When 2 of mine were about that size in a 50g is when they began to really spazz out and jump and hit the lid of the tank, or the sides of the tank. It didn't take much to spook them
 
I was kind of wondering if it could be self-inflicted by jumping, but I haven't noticed any of that. And since the aquarium is in my office I imagine I would have. It is now "lights out" over here in Europe, and I find myself constantly checking on the poor guy. So far so calm. I hope he lives long enough for me to isolate the problem...
 
BTW, I'd like to say thanks for all the replies! This is my first trip to this forum, and it seems like a really pleasant and helpful place! I think I will stick around and learn a few things!

Cheers!
 
Just keep an eye on them and keep the water CLEAN. I took a second look at that picture and it really looks internal.
 
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