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Planning First Octo tank


Aug 7, 2019
Jersey City, NJ
Hey guys, this is my first post on tonmo. I've lurked here for a while and finally made an account back in august and
I'm finally ready to start planning my first octopus tank! I've kept several reef tanks and currently have a 40 gallon SPS tank and a 10 gallon nano mantis tank.
I have a move coming up soon, so the plan right now is to break down the SPS reef and give the corals to my brother, keep the mantis and begin cycling the octo tank once I move.

I was considering getting a 60g biocube type (i'm not sure they make them anymore) just for ease of octo-proofing, with the size depending on the species, but I'd heard that lateral space is preferable to vertical space in some cases. Does anyone have any experience with cubes? Or would it be better just to octo-proof a regular tank?

As far as species go, I was thinking about going for a briareus. I work mostly in the evening and I'm up pretty late. I was thinking of getting one from mysaltwaterfishstore. Would it be better to source one locally? I'm in the US Northeast. Any advice would be great, I want to do my first octo tank right, and give the animal a good quality of life.
Well, since home-kept octos are benthic, it would make sense to favor lateral/horizontal space vs. a tall tank. Hopefully some of our resident experts can weigh in here! We do have two species available for sale right not (bimac and o. rubescens), not sure if those would meet your needs.
O. briareus is a good choice for your schedule but you definitely want long vs tall as they typically have the longest arm span of any of the Caribbean octos (and of most of the octos we, regardless of water of origination). Look through the posts in Posts with info for New Octo Keepers for some general getting ready ideas and through the Tank Build Outs thread for some tank and octo proofing ideas (please consider photographing and logging your build out in the Tank Talk forum)
Hey guys!

Sorry for the delay. Thank you for the advice. A non-cubular 55 or 60 seems like the right move then. I don't have a lot of experience with plumbing and sumps, and from everything I've read a sump is almost required right? Either way it'll be a blast to do. I'll start reading up on it.

As far as species go briareus is ideal, and I found one not super far (2hr drive), but they've had it for some time now, and I'll be moving in what looks like March now. So that plus the 3 month cycle might be too long of a wait. I saw you guys had a bimac and a rubescens for sale! They're cold water though, and I'm a bit apprehensive about getting a chiller. Still on the fence though.

I'll keep you guys posted as I get closer to the move! I'll make a build thread!

Thanks again!
One basic thing that is often overlooked when planning a tank with a sump is the clearance between the shelf holding the main tank and the top of the sump. Bigger is always better for water volume but you need enough clearance to hang a skimmer AND easily remove the collection cup.
Hey guys, thanks for the advice! I've been doing some planning and I'm thinking a 20 gallon sump with a bean animal overflow. Would a 20 gallon suffice?

Also I've been looking into drilling a 55 gallon and everything I've read says it's a gamble without figuring out which panels are tempered. I heard that tanks with a bracing bar don't have tempered side panels. If that's the case I'd go with a 60.

When youre planning a tank, do you usually plan for a specific species? If I plan for a bimac, should I start the cycle at tropical temperatures and then gradually drop to temperate? And for lights a t5 fixture would a t5 fixture be too much? even for a nocturnal species?
If you are planning a tank for a bimac, you should let the tank circulate and get established at a temperature appropriate to encourage growth of the beneficial bacteria (between 77-80 deg) for the first few weeks if you have the time. After that, you can drop the system temperature to a range that is more comfortable for a bimac (60-70 deg).

When it comes to drilling glass tanks of that size, I would be very careful. I like to work with acrylic tanks for this reason, so I don't have much experience drilling glass so hopefully there are others who can help you.
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