Hello, I am new to the octo world, but would love to set up a tank and give it a try. I am guessing that Bimacs are the most common since I read about them the most. How big do these guys get and what is the smallest tank you would keep them in? I would like to do a tank w/ lots of LR and caulerpa which brings me to my next question; what do most people use for filtration? Also, what is the secret to keeping them from escaping? I look forward to hearing your answers as it seems that there is a great group of knowledgable ceph lovers in here.