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O. mercatoris babies!


O. bimaculoides
Oct 19, 2006
I bought a very large (for her size) O. Mercatoris a couple of months ago. She laid eggs, which she then abandoned. Then she concealed herself in a hole in the rock. I was very depressed, knowing she would die soon. but, in a miracle sort of way, on the 24th I had discovered several nice, healthy Mercatoris babies. They are eating the hordes of amphipods in their tank. I am aware they are cannibalistic, so I tried to separate them using breeder nets, but they are crafty, and got out. How do you guys suggest to house them separately and still get good water quality out of it? they are wonderful creatures, and i would hate to lose them.

Thanks in Advance,

P.S: Pics will come soon.
ok off topic question how do i get mine to have babies i dont know if mine is a guy or girl and how do i know weather im going to buy a guy or girl i have a ceph
There's no perfect answer here - you might try a few in breeder nets, and leave some to grow up in the tank. How many do you have? Danthemarineman reports several living under the same rock in the ocean, but we have less luck when we try that in our tanks. Do you risk running out of amphipods? They will only take live food for a while. (Correction: They may take non-life food if offered after they've grown a bit.)

Is the mother still alive? - she might live on for some time, so if she is still alive, you should try to supply food.

Yes, the mother is still alive, but she does not accept food. There is a small risk of running out of amphipods, but I have quite a bit and am ordering some very soon. What do you mean by "they will only take live food for a while"? Does that mean they will cease accepting live food, or I could get them on frozen? Before the mother was guarding her eggs, she ate frozen.
"they will only take live food for a while"

To rephrase it, "they will only take live food for the first part of their life and then will possibly accept frozen food later when they're bigger."

Most young octos don't readily take frozen (thawed) shrimp, krill etc. But won't hurt to try as long as you don't leave it in there to foul the water. If they don't want it.....take it out.

They will never cease to accept live food
I sent Kathy aka Indiana OCHO a mother O. Mercatoris and her eggs. She had success with the babys. She also got the mother to eat frozen shrimp. You could ask her for tips. I would leave them all in that tank and provide lots of live food and lots of stuff to make dens out of. Like shells or small pices of pvc. I have had 20 or more in the same tank.
Dan, you're absolutely right - some octopuses never accept dead food, but most will eventually. They will need larger food after the amphipods. Most people buy small crabs and snails for the live food and try thawed frozen shrimp (or even fresh shrimp) for the non-live food.


I cannot thank you enough for your advice. I have decided to use the "shotgun" approach, I separated 10 of the babies into breeding containers, and the rest (10-20) I left in the tank to grow. So far, the ones in the breeding containers are eating amphipods, mysis, and Collonista snails. How fast will they grow? I was thinking when they get larger, I'd feed them Shore Shrimp, P. vulgaris, and once they get even bigger (full grown) I will feed them Fiddlers and Various Frozen Foods (if they accept them). Does this sound about right? I really do hope they survive, I really enjoy watching and caring for them.,
Sounds fine - good variety in the food. I'm sure your little mercatoris will enjoy dinner!
Keep us posted on their progress, please!

I will try to update daily if I possibly could. i will also try to incorporate pics and maybe a couple vids too.

Day 6: There has only been two (visible) deaths, and these were the octopi that were attacked by their siblings that I left in the tank. There are still quite a few left in there, and hopefully they don't eat each other, as there are quite a lot of places they can hide. The ones that I separated are still alive and well. they are eating Amphipods predominately, and some Mysis every once in a while. There are Collonista snails in with them, but they don't seem interested in eating those. I have 15 in the containers, and about 10-20 still in the tank. Mom is still alive, but not accepting food. I am ordering 120 amphipods today, and have set up some tanks to breed them in (the amphipods)
Wow! You've got quite a handful of very very cute little guys there. It looks like everyone's doing well too. I wish the best of luck and look forward to following this endeavour.

Cheers, Jesse

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