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New 90-gal Setup for Octo

Dec 3, 2006
93.5064931 US gallons.
48 in. x 18 in. x 25 in.
AGA Fluorescent Strip
3" of fine sand?

140 lbs Fiji live rock
50 gal fuge with chaeto, skimmer, heater, various other cleaning crew & whatever live rock rubble comes out of four 35 lb bags

Does all this stuff sound okay for an O. bimaculoides, or maybe O. vulgaris?

A few questions about the vulgaris (if this tank is even big enough to keep one) - is it diurnal or nocturnal, and what temperature does it enjoy (the only # I read was from a ceph care article that said 25C)

I live in NY so my biggest concern is the temperature not being cold enough for the octopus. The tank is going in my basement which generally remains between 60 and 80 degrees in the winter/summer. Is this something I should be very concerned about? Do I need to invest in a chiller, or should a fan be enough?

Most Important Questions
a. Can I definitely keep an O. bimaculoides in this?
b. Do I have to be very concerned about the temperature?
c. Should I use fine sand? And how many inches of it?

Thanks for your replies!
I think the system sounds pretty good for a bimac, but probably is a touch small for a vulgaris. Cephs create a lot more nitrogenous waste than most creatures, so have some back up bio filtration ready in case the live rock doesn't cut it. On the other hand, 140 lbs is a lot of LR, so I suspect you'll be fine unless your octo turns out to be a "super bimac" (which has happened but doesn't seem common). I don't know much about vulgaris so I won't pretend to be knowledgeable about them.

Temperature is a big thing for a bimac. Their natural habitat ranges from 59 to about 70 degrees. Using a fan on the sump is an efficient way to bring temperature down, but if it doesn't do the job in the summer you'll have to face getting a chiller or really cutting into the animal's lifespan. I kept some tropical cuttles this summer, and even at a little over 80 it cut a couple months off their lives compared to some of their siblings elsewhere.

I use sugar-fine aragonite sand, but I don't think it matters too much. Bimacs are intertidal and are used to crawling over all sorts of sand and rocks. An inch should be sufficient.

Good luck,

Actually, my basement is generally 57 in the winter and doesn't get hotter than 72 in the summer (those are the exact numbers that we run on the central A/C in winter/summer, respectively).

In the summer, with a fan, I should be fine then right?
Also - I've always wanted to keep a Red Emperor Snapper, but I know those guys grow way too big for a 90-gal.

What do you think about this?

1. Get the tank next Monday (Dec. 18th)
2. Set everything up, order the 140 lbs of live rock
3. Cure the live rock in my tank for 2-4 weeks
4. Order a red emperor snapper from saltwaterfish.com, 5"-6", and keeping him 'til he outgrows the tank (a few months)
5. Trade him into LFS and get a bimac?

Edit: I'm thinking either panther grouper or red emperor snapper would help me fully mature the tank for an octo faster since they produce a looot of waste. Don't worry - the tank will be cycled before I put the fish in, it's just a matter of maturing it enough for an octo. Comments?

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