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How big could a bimac get in a 240 gallon


Staff member
Nov 20, 2002
Your bimac will enjoy living in a large tank!

THis is what you find in Cephalopods: A World Guide

Body 5 inches, arms to at least 14 inches

However, we had some that grew considerably larger. My bimac Ollie weighed over three pounds at the time of her death, had a mantle more like 7 inches and arms that were more like 20-22 inches. It's hard to measure an octopus because they change sizes so easily.

I think the reason she grew so large was heredity and also very good quaility food including live food every day.