• TONMOCON VII Announced | MBL at Woods Hole | Apr 6-8, 2018
  • Thanks for visiting! TONMO is the world's greatest online cephalopod enthusiast community, with interactive content going back to May of 2000, and a biennial conference. If you'd like to join in on the fun, become a TONMO member -- it's easy and free. You can follow us on Facebook and Twitter for more cephy goodness.


What size tank do I need?

Hayek

GPO
Registered
Joined
Mar 9, 2009
Messages
130
#1
Hi guys,
I was hoping someone could give me a bit of advice.
I have a 55 gallon tank at my disposal, but it is within my budget to set up a 125 gallon tank for an octopus. Would this be an overkill - way too large for what I'm likely to get?

I've seen quite a range as to what tank size I might need to keep an octopus in. Some places say I need a 40 gallon tank, Tonmo says 50 gallons, and some other places say 125 gallons at a minimum.

What size tank would I need for a:

Bimac:

Briareus:

Hummelincki:

From what I have read, saltwaterfish.com advertises briareus but sometimes sends Hummelincki.

Also, I can't find anywhere that sells Bimacs, anybody know a place? They sound a bit friendlier than the briareus and hummelincki.

I'll continue lurking and see if I can find some answers, but any help would be greatly appreciated.
 

DWhatley

Cthulhu
Staff member
Moderator
Joined
Sep 4, 2006
Messages
19,891
Location
Gainesville, GA
#2
Hayek;134233 said:
Also, I can't find anywhere that sells Bimacs, anybody know a place? They sound a bit friendlier than the briareus and hummelincki
You obviously have NOT read my hummelincki journals :sagrin:

For all of the above a 55-75 gallon tank is acceptable and you could get by with a 50 for a hummelincki (where the longer arms of the Briareus would be more comfortable in a 75 but they have been successfully kept in a 55). The 125 recommendation is likely for a Vulgaris and that may be too small depending on the animal (the Caribbean seem to be smaller than the Mediterranean).

How big you want to go depends a lot on you long term use of the tank. An octo tank is most successful as a species only tank with a minimum of low stinging soft corals so the extra room may be a disappointment. Personally, I would suggest something between 55-75 with a 30 gallon sump (OhToo's tank is a 60 with a 35 sump and has been my best Octo setup, the 45 hex I have for Beldar being second best but needs a smaller octo than the ones you would like to acquire).
 

Hayek

GPO
Registered
Joined
Mar 9, 2009
Messages
130
#3
Oh! I did read some of your Journals - I just didn't see anything about tank size. You have kept some beautiful Octopodes. Thank you for taking the time to post the information, it is some of the best I have found online as of yet.

I was thinking that I should just go ahead and get a 125 because I have had quite a few tanks in the past, and each time I have wished I had gone bigger. Might it be possible to keep more than one in a 125? I've read they can be cannibalistic if too many live too closely...

I may just go for a vulgaris - any advice on tank size for that?

Also, I know that I can't put them in a tank that has been treated with copper, but what if I buy a used tank that has had copper in it before. Would it be sufficiently diluted not to hurt an octo or would I be better off just going with a new tank?
 

monty

TONMO Supporter
Staff member
Supporter
Joined
Mar 8, 2004
Messages
4,887
#4
Cephs are so sensitive to copper that our recommendation is to not risk any used tank that has had copper. The copper meds seem to get stuck in the tank, probably in the sealant, and leach (leech?) out slowly into the water, often at levels that can kill a ceph, so we recommend the "better safe than sorry" approach. Similarly with keeping more than one octo, it does seem to work out sometimes, but often one animal is lunch for the other, or, if they don't get along, they'll both be stressed and hiding all the time. Lately, people seem to be having better luck with multiple octos (maybe because Mercs are less prone to these problems than other species) but it seems like it's better to have one octo than to risk the problems with having two... these animals are solitary in the wild, so it's not really likely that they'd want "companionship" or anything.
 

DWhatley

Cthulhu
Staff member
Moderator
Joined
Sep 4, 2006
Messages
19,891
Location
Gainesville, GA
#5
I'll second Monty's comments on keeping two in a tank. The only successes with this have been people raising octos that have lived together before going into an aquarium or are sibblings born in an aqurarium. Mixed species has been a disaster. There have not been many attempts over the last few years of same species pairs from different enviornments so the jury is out on that possible combination (Domboski the only one I remember that tried and the male aculeatus died for unknown reasons).
 

Hayek

GPO
Registered
Joined
Mar 9, 2009
Messages
130
#6
Thanks for the great information. I found a cheap tank second hand that has never been set up - a 47 gallon bow front - and I will be setting it up to cycle this weekend. I doubt I will be able to wait a full three months before putting an octo in the tank, but I will test ammonia, nitrite, and nitrate daily to ensure a mature nitrogen cycle. Sometimes I can speed it up a bit by soaking bio balls in cycle. We'll see. I'll keep you posted.
 

Jean

Colossal Squid
Supporter
Joined
Nov 19, 2002
Messages
4,218
Location
Dunedin, New Zealand
#7
Hayek;134353 said:
Thanks for the great information. I found a cheap tank second hand that has never been set up - a 47 gallon bow front - and I will be setting it up to cycle this weekend. I doubt I will be able to wait a full three months before putting an octo in the tank, but I will test ammonia, nitrite, and nitrate daily to ensure a mature nitrogen cycle. Sometimes I can speed it up a bit by soaking bio balls in cycle. We'll see. I'll keep you posted.
PLEASE, PLEASE, PLEASE try to be patient and let it go through it's complete cycle! Octopus produce mega waste for their size and an incompletely cycled tank is very likely to crash, in my experience there is no way to speed up the cycle in an octopus tank!


J
 

Members online