would a male reddevil be alright in a 40 long by itself with alot of filtration because they are the lenths of 55 or 75 and i think its reasonable do u guys think so.I plan on putting two aquaclear 200 filters on the 40 gallon.
The foot print would most likely be ok but a fish that big would eventually just pollute the water more than the filtration could handle. I agree 75 gallon minimum for them.