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New guy question


Pygmy Octopus
Oct 15, 2005
Hey guys. Last month I received a shipment of liverock from Tampabaysaltwater.com. It was absolutely magnificant!! For anyone needing liverock to either start a tank or just top off a tank there is noone better. The prices are great and I have never worked with anyone better and more helpful than Richard. Anyway, now that its been about a month since I set up the liverock, all kinds of little critters are coming out to be seen. I've seen featherdusters, gorilla crabs (:mad:) and many other cool species. Last Saturday night at about 11:30 I was looking around in my tank, and notice something that I hadn't seen before and wasn't there earlier that night, an octopus!! I am not sure what species it is, but I think it is a dwarf species. I will post a couple of the better pictures I took so maybe you all can help me out.

Anyway, I say all of that to ask this. I know it is hiding in the liverock somewhere, and I was wondering if any of you would have any small tricks that I could use to coax it out of hiding. It is my main tank, so I would rather not reverse the light cycle just yet. I have extended the "night" an hour, and I am going to buy a lunar light earlier than I had planned, but I really don't have any other ideas. Anything you all can give would be helpful. Thanks.

I have always wanted to get an octo, and had not yet had the opportunity, so this is very exciting to me. I want to do all I can to make this work.

Also, about a week ago, I saw a link to a website where I can buy crabs cheaply for food. If anyone has that link or another, I would appreciate it greatly.
The octopus you got is most likely O. Mercatoris or O. Joubini. Both are dwarves that can be found in Florida. I haven't heard that reversing the light cycle will do anything; unless you are wanting to be able to view him during the day, which probably still wouldn't work due to the ambient light. www.aquaculturestore.com is the place a lot of tomnoers get their fiddlers from. For now I would wait for him to eat all the critters on the LR (perfect to get rid of the gorilla crabs, if he's big enough that is) before you buy food for him. Dwarf species don't live long (usually about 6 months, maybe a year, but that is from birth) are almost always nocturnal, and just not as fun as the bigger diurnal octos that are good for aquariums. If you set up the tank for an octo, I would wait for this one to die (I wouldn't think it would be too long) before you put one in. That should be about the right time anyway since the tank should cycle 3 months. If you were going to do a reef, wait til he dies before you get anything you wouldn't want killed. Also I wouldn't do moonlights yet either. If you want to view him at night you can get red LEDs. Blue light is really bright to an octopus and red is very dim. With regular moonlights you probably have less of a chance of seeing the octo.
:welcome: to TONMO. Looks like shipposhack covered your questions pretty well already, so I'll just leave it at that...
Hi, and welcome to the site!:welcome:

Yes, you're lucky to have a hitchhiker octopus. This happens from time to time with Florida live rock becasue that's where these little octopuses live. Most likely it's O. mercatoris.

Hold off on that lunar light - blue light isn't good for octopuses. To observe a nocturnal octopus, you need red light. I had success with a flashlight with a red lenscover.

You might find this thread very useful - it's dwhatley's description of the lives of her tank raised mercatoris:
[Octopus Eggs]: - Trapper's Babies - Tank Raised Mercatoris

Your little octopus will most likey find food in the tank for a while: amphipods, snails, crabs, even shrimp. You might get him to accept pieces thawed frozen shrimp or even krill.

Good luck with your tank and please keep us posted.

If your little fella is a Merc, (here I go again:wink2:) get a block of FROZEN Cyclop-eeze, thaw a quarter to half dollar sized piece, dilute with about 1/4 cup of saltwater and use a pipette to put it in the tank after ambient lights out. If you want to watch what happens, use a red light :grin: to light the tank (it can actually be pretty bright but it must be red - LED's work but a red filter - I have even used a Folgers Coffee can in a pinch - seems to be just as good). If you do this nightly (feed over at least 15 min) you will have your octo waiting for you when the lights go out. If you are lucky you will see him/her as well.

Unfortunately, as Shipposhack mentions, he/she is likely to be full grown and at life's end. If you start seeing him during the day you will have a week or less from that point but since he/she is still avoiding the light you should have some time left to enjoy him and learn.

My five tank raised babies are 6 months and 11 days, are roughly 3" long and show 5 very different personalities. Three I see every night, one is interactive. Sistrurus comes out within five - usually within 2 - minutes of the time I sit down to feed, Miss Broody does not leave her tank front den and is visable 24/7 and actively feeds, Medusa only shows her arms at feeding time (sometimes I see eyes), HideNSeek lets me see him about twice a week and Mia is almost never seen.

Their mother was rarely seen until she started brooding (I did not hand feed Cyclop-eeze until after the babies were born). After three months she took up residence in the same barnicale as the baby that is always visible and does not leave her den, laid and started brooding her eggs and lived for 11 weeks after the babies were born. Her story is also recorded in the journals - look for Trapper is Finally Here as a title if you care to read more.

I have yet to have a real octopus (OK, so nobody else has said that - at least not in front of me :smile: but I do acknowledge that there is quite a difference) but have learned a lot about octo keeping with my little group and will likely continue to keep a dwarf or two even after we octo-convert our largest tank (the tank we planned for a midsized octo now has three dwarf and I am hoping they breed so we have to come up with another tank to house what we had hoped to get in the first place - no regrets though).

Good luck and please journal your experience!
You have a "real" octopus, and all the more power to you for being such a good keeper (and documenter) of the little mercatoris. Still, I think you'd enjoy having a larger, more interactive octopus and I hope you're able to sometime.

Could you please explain what you meant by the Folger's coffee can?

While I appreciate the food suggestion, does anyone have any suggestions for food that won't cost me $200? Don't want to sound cheap, but I don't know how long this guy is going to me around, and can't afford to spend that much money on fish food.
The local pet store here sells feeder crabs at like $1.00 - $2.50 each. See what the ones around your area go for, Im sure u can get food alot cheaper than $200
Folgers coffee comes in a red plastic coffee can. I think I buy the brand just for the cans as they are SW safe and get used for everything from emptying my shrimp tank to freshwater dipping. If you put a regular light inside (it does need to be fairly bright but not hot), you have an instant red light :wink2:. I used this for almost a month before I finally came up with the red filter for my existing light on Sistrurus and Medusa's tank.

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