• Looking to buy a cephalopod? Check out Tomh's Cephs Forum, and this post in particular shares important info about our policies as it relates to responsible ceph-keeping.

Why a 55g?


Jul 21, 2004
I was curious to know why a 55g is the tank Bimac keepers specifically
recommend for keeping one. I know that the 55’s I see are usually tall
and skinny. Isn’t that the opposite of what we are opting for?
Since Octopi are primarily bottom dwelling, I would assume that the most
suitable tank would have the most bottom surface area. I also realize
that this is the minimum tank size that we are talking about- but
if most 55’s aren’t exactly the ideal shape then why don’t people
recommend a smaller or larger tank that is commonly made with more
Octo friendly dimensions?

Thanks! 8)
Well, I think you kinda answered your own question... :wink: I have one of those off-dimension 55s, and it IS something of a pain. Frankly, just for general aquariumkeeping, it's too tall to reach the bottom at all easily, it's too narrow to put any liverock in it without taking up basically all the bottom space...just annoying. It was free, which is why I can't gripe too much. I was under the impression 55gals of these dimensions weren't made much anymore, though...

Anyway, 55 gallon is mentioned because it's a good minimum and because it's such a common size. These days, I'm seeing so many innovative tank shapes and designs that I'd think you can prolly find one in something close to 55 that strikes your fancy.
Actually, it's a 50 gallon we're recommending as a minimum. You seem to be able to find a variety of shapes.

If I had one thing to change about my set up, I'd have a lower cabinet so the overall height would be lower and I could reach in more easily. I saw what how Debbie (dbbga) was keeping Jetta, and the tank was lower and it was so much easier to take care of or to play with Jetta.

But, most cabinets seem to be taller, perhaps to accomodate protein skimmers.

One of my pet hates with the american shops is the way that the tanks are sold by their gals... as you pointed out it isnt very clear what the tank actually looks like...

Over here, tanks are always sold in good old fashioned dimensions AND in inches :smile: no mistakes there...

So that means that 48x18x15 gives approx 50 gals once you take away 10% for displacement
Well, everyone knows you Scots have all the luck... :wink:

Actually, I have a somewhat related question--curved tanks. Any experience with these? Depending on the design, some are even glass, vs. acrylic, but either way, I would think curved panes would be much harder to algae-scrape...especially coralline...
Oh...I thought the mininum tank size for an octopus was 35 gallons....
That's what I even heard on this forum, but mabye it changed.
I might get a 75 gallon tank just to satisfy the octopus...lol. That would be best.
I have a glass bowfront, which means that i have a gently curved glass front.

For some reason, my coralline algae has always formed only on the sides of the tank, which are flat. I frequently clean the front with the cleaning magnet and have no problem. The hard sponge-type cleaner works well, too.

I've noticed a couple of things about the bowfront - It optically changes your view, and you have a better view looking into the tank. However, being curved, it sometimes makes pics hard to take. I have to take them at an angle.

I like the curved glass a lot. It helps me sit at my PC and get a good view inside the tank, and it looks a little more elegant in the diningroom than many rectangular tanks.

I've been thinking of upgrading for a while now, and I've been leaning toward a glass bowfront like yours...hence my inquiry... :heee:

Can't afford this just yet. And I think I'm going to have to ask a woodworking friend to help me build a stand (a MAJOR project... :shock: ...but I've got a budget to think of...)

Shop Amazon

Shop Amazon
Shop Amazon; support TONMO!
Shop Amazon
We are a participant in the Amazon Services LLC Associates Program, an affiliate program designed to provide a means for us to earn fees by linking to Amazon and affiliated sites.