I've been setting up a salt water tank fairly slowly but this Friday I'm going to have the last of the live rock I wanted to buy for it (i'm getting 90lbs total) and am going to leave my tank to cycle until the summer before I put anything in it. It's a 75 gallon which I have read is more than big enough for a bimac which I hear most people keep in 50 gallons, but I still have some uncertainties about this Octopus. From what I've read, the Bimac can have a mantle length of up between 5-7 inches and 23 inch tentacles, but from the pictures and different posts I have read I've never seen one that looked to even be close to that big to me. I've heard many things on these particular octopuses and I've heard of many people having them be 7 months old and only having a mantle the size of a golf ball which comes nowhere close to 5 inches let alone 7. Do Bimacs actually get this large or are some of these smaller octopuses not actually Bimacs or what? This leads to my further question about feeding a full grown bimac if they get as large as I've read that they do. I have no problem having a supply of some small fiddler crabs and have a 20 gallon that I'd keep them in and can keep filtered between feedings, but most fiddler crabs I've seen are maybe 2 inches long at the max, so I don't see how a full grown bimac could make a meal out of such small crabs. Do bimacs just not get as large as I read or do you just have to feed them larger things than fiddler crabs eventually? Thanks