• 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.



Aug 24, 2009
i'm getting an o. mercatoris. the only problem i have is the feeding. behind my house there is alot of fidler crabs running around so i sopose i could just use those. but they're so small i don't know how many to feed him or if he will even eat them.

how many will he eat, (asuming that the fidlers are about the size of a dime)?
will he eat them?
and, if i let afew more fidlers than i should into the cage will he eat them all or save some and not eat them?


Staff member
Sep 4, 2006
Gainesville, GA
Yes, mercs will eat fiddlers as a primary food item and one dime size is a good daily meal. You might buy a packet of the larger (PE is my preference but Hikari also has a larger size) mysis shrimp to give it a change of menu. I have not kept extra's in the tank with the mercs so I can't give a direct experience but others have reported excess crabs and sometimes snails have been killed but not eaten by other octos. I don't know that this would apply to the mercs but should be something to watch. I would not put extras in at all until you have had the animal for two weeks and it has adjusted to tank life, then you might experiment and hopefully record a journal entry on what you experience.


Pygmy Octopus
Nov 2, 2009
i have a wonderpus that i have owned for about 2 months and she seems to really like frozen cocktail shrimp! i will cut the shrimp into 4 pieces and feed her two of thous pieces a day. the best part is she'll let me hand feed her the pieces. i say give that a try, cause when i first got her she wouldn't eat any of the crabs or damsels i had in there for food.

Members online

No members online now.