The "one inch per gallon" rule

  • We are currently upgrading MFK. thanks! -neo
simple version= fish can turn around and swim straight, tank is fine
 
So is the "one inch per gallon" the same as "one drop per gallon"??
 
wonder if there's a rule for length of fish = footprint of tank, for large fish. Like tank length = 3x fish length, tank width = 1.5x fish length, tank height = 1x fish lenght or something like that.
 
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