Devil's advocate here: why is it when people ask how many bichirs can be housed in a 75/90/110 gallon tank I always read 3/5/8/10 bichirs? Why? Assuming the 72"X18"X19" tank is used for upper jaw species bichirs only (except weeksii & ornates), and assuming filtration is up to par (BIG ASSUMPTION HERE), water changes, good varied diet, etc. -- why wouldn't you be able to HAPPILY house lets say 20 or 30 bichirs? Bichirs in large numbers tend to do very well together & it reduces aggression as well. Is 20-30 bichirs not reasonable here? I think it is. What are your thoughts?