Every species is different - you can observe and learn from all of them. Briareus is not kept as often as bimaculoides, partly because its usually wild caught.
Bimacs need a cooler tank, but briareus is a more tropical species.
Briareus is nocturnal but may eventually come out in the daytime. It has a beautiful irridescent tone at times. In order to watch its activities, you can install red leds or even moonlights so that you can see it at night.
his mantle is a little over an inch and his arms are about 8 inches all streched out.
i this the largest he can get is 24 inch arms but not too sure about the matle.
my talk is 78.7
i would pry bring your tank up to atleast 77 because he is a carribean reef octo.