It's been awhile since I last updated this thread. Here is a picture of a new piranha I got the other day. He is a Caribe Piranha. He is still a juvi and I am growing him out to one day put him with my red bellies. He is by far the most aggressive piranha I have ever had. He doesn't hide and will chase your fingers. A Caribe piranha is very similar to a red belly but as you can see they have black spots and clear eyes. They are also more aggressive and can grow a little larger. They do however belong to the pygo family just like red bellies and can cohab. One day he is going to be the boss of my piranha tank.
I also recently picked up a baby eret goby. I have been pretty bummed out since my last one died and was happy to find this new guy. He hides a lot so I haven't been able to get a picture of him yet.