[Gracie6363]

Well this 40 gallon tank that I recently recieved came with 8 fish. 5 red minor/serpae tetra's, 2 leopard cories and a pl*co. I am usually facinated with new fish in the tank, but I had seen these at my sister in laws each time I went over so they weren't anything new to me. Since, I have added a few new fish and I have had more time to sit and observe all the inhabitants now.

The 5 tetras all had nipped fins when I got them and they often chased the other tank mates. That's all I noticed at first. I couldn't even tell them apart. The last few days I have been watching more and seeing differencs.

A few of them have darker color or black right at the base of their body before the tail starts. 1 or 2 of them are swollen in this area. One that is the most swollen, it's top fin also seems either clamped or torn. Hard to tell. But it's been that way since he arrived. They are all active, eating and seem happy, but I am concerned that it's disease. I haven't ever experienced disease really... Had ich once.

Can anyone help me with this?

my tank is PH 7.2 Temp 76 Ammonia .25 PPM Nitrite 0 PPM