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New to Cephs: Just got a Mercatoris

Hi everyone. Inky has been with me since Sept 30, so 2 months now. His night time activities are hilarious, he's very very active - are Octopuses supposed to be that active? However he hangs out on the front glass of the tank and my camera is pretty much recording him every few minutes (motion activated). He doesn't quite explore the rock pile or sand or anything else, just hangs out moving around all the time on the glass pane. Curious. I thought he was bored so I got some hamster tunnels and have a hermit crab in there. I tried putting fiddlers but they manage to escape.

Yesterday he said hello to my finger, he tried to pull me in, such a strong little guy. I'll try again.

@pkilian the smallest crabs are quite a big meal for Inky, here's a video showing him getting scared by the crab

I don't know what to do to make hunting easier for him, I mean he's an octopus, shouldn't he be a terror to crabs? Should I incapacitate the crabs, make it hard for them to scurry off?
Cruising the glass is so common to octopus behavior- my tank is set up in my living room, so in our situation glass cruising seems to happen when something interesting is happening in the room- especially dinner and tv time! I know glass cruising can be a sign of boredom, but that’s not always so! Does your camera have any lights on it that blink while it’s running? That could be a draw for Inky!

When I feed fiddler crabs, I cut off the big pinching claw- but even that might be overwhelming to a small octopus. Do you have hermit crabs in your tank? My mercs have always liked those...
This is one of the smallest fiddler crabs in my crab bin. He's pretty large for Inky. Should I incapacitate the crab a bit more for the next meal? Inky gets scared and jumps a foot in the tank when they charge at him, and this is after the big claw has been removed.
Please advise
@squishy2020 My apologies for my late reply. Things have been busy for me recently :)

My recommendations for feeding fiddlers that are too large for your octos is to kill the crab right before you offer it to Inky and use a stick to offer the dead crab to them. You can do this easily by inserting a wooden or plastic stake into the crab carapace at the back of the crab where the top and bottom of the carapace meet. I can post some photos of how I prepare my fiddlers for my octos if you would like.

I use a sharpened zip tie that's about a foot long and spear the crab with the end of the zip tie. Then I offer the crab to the octopus while it is attached to the feeding stick. The easiest way to trigger a feeding response is to gently touch the crab to the sucker cups on the octopus' arm. They have a lot of contact-dependent taste sensors on their sucker cups, so if you touch the prey item to their arm it will often trigger a feeding response. If you touch Inkys' arms with the crab and they push it away or run away from you, then remove the crab and try again in a few hours or the next day.

I agree with @sedna that the crabs are a bit large for your animal, but if you kill them with the zip tie or wooden skewer before you offer them to Inky then you shouldn't need to worry about freezing the crabs and separating them into pieces. Inky likely won't be able to eat the entire crab, so make sure you remove the shell and remaining pieces of the crab shortly after they are done eating so that it doesn't harm your water quality.

If you have troubles with Inky grabbing the stick and not letting go, you can try to use the air-water interface (essentially the surface of the water in your tank) to encourage Inky to let go of the stick. This is done by slowly lifting the stick out of the water while the octo is holding on. They will likely let go of the stick and move so that their body remains in the water. If you are doing this, be careful to leave their mantle and gill openings under the surface of the water so that Inky can still breathe. You may not have troubles with Inky letting go of the feeding stick, but especially curious animals will grab onto the stick and not want to let go. Send a message if you are struggling with Inky letting go of the feeding stick and I can give additional recommendations.
@pkilian @sedna Thank you

I tried freezing the live crab and feeding a piece and Inky wasn't interested, I've also now tried a piece of scallop. I have raw shrimp in the freezer which I will try next but I will also try the skewering a live crab method.

I recently got a boat load of dwarf cerith snails, dwarf planaxis snails and also hermit crabs so he's likely snacking as he feels like it too.
Finally got to listen to your podcast, @squishy2020 -- really great stuff! Thanks for the TONMO shout-outs and it's great that you got to get support from the legend that is @Thales. :mrgreen:

For those who missed it, this is a great interview that goes in-depth yet is also a well-rounded assessment of what it takes to keep an octopus:
Great! Thanks for taking the time to listen. Inky is such a character, if he wasn't nocturnal, I would t ever get any work done. They are fascinating intelligent and beautiful animals. I'm quite privileged to have had the chance to keep one.

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