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tank size for hatchlings?


Mar 10, 2020
Hello! I'm working with Octopus bimaculoides and looking at trying to rear some fertilized eggs. I would like to raise them in different tanks than the adults are housed in for logistical reasons (mostly to prevent them from going into the filtration system, but also to better track their feedings, keep track of them, etc.), but all recommended tank size requirements I find are for adults and suggest 50+ gallons. Has anyone raised hatchlings in smaller setups? If so, what did you do, and how did it go? I'm wondering if a smaller tank with a built in or hangover filter (i.e. a small standard home aquarium) would likely work the first couple months.

Any info is much appreciated!

Hi Kelly/@dolfinnk, thanks for joining TONMO! Hopefully you'll get some expert engagement here on your project - do treat this thread as a journal of sorts; even if you don't get responses, I do know that people are reading :wink: ... Meanwhile, here's a thread from the past that you may find helpful:

Also, you can filter the Cephalopod Journal forum based on prefixes, so here's a link to that forum with the Octopus Eggs filter on:

Keep us posted, thanks!
I have only raised a few O. mercatoris (Gulf dwarfs) and one pair of O. briareus (survivors of eggs laid in my tanks from wild caught mom).

The mercs are small as adults and are often found in close quarters so that experience may not be relevant to tank size but my broods were initially born in a 45 gallon tank but the hatchlings were kept in groups of 5 (or so) in large breeder nets at the surface of the tank.

With my one larger success, I experimented with all sizes and circulations (including a foot bath) for the hatchlings. The ones that ultimately survived were kept in 55+ gallon tanks. All the animals in the smaller tanks died quickly. The animals in the 2 larger tanks survived longer but, likely due to cannibalism, only two hatchlings survived to become full adults (one in each of the tanks).

Bimacs are not as cannibalistic as briareus and at least one keeper kept them together successfully in a large tank until they were old enough to be placed in new homes (several months). One pair survived living together to adulthood.

Here is a dated but still relevant list of experiences and articles about raising hatchlings. The information by ZyanSilver will be specifically about his success with bimacs.

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