I feel bad because I used to have 5 tetras in one of those 5 gallon water bottles with the top cut off but i didn't really take that good care of them. It was around the same time i got my 55 and i was still a beginner. Those 2 i have now were the ones that survived. One tetra died when the tank cracked. It was my fault. I was being stupid. It only happened a few months ago.