true as this might be, this reasoning makes all fishes acceptable for combining them - given enough water, even white sharks can be kept that way (take a large lake, drain it and refill it with see water. I'll leave the rest for imagination)
I have a 4 meters tank, that is 13 feet. This tank is nothing compared to even the tinyist river one can find in nature, but it is huge to have in house.
I consider it a tank, and I do realise I can keep only a limited amount of fish in it
