[Octopus Eggs]: Legs - O. Mercatoris

04/28/15 - Counted 5 hatchlings in the tank this morning. Have not seen the one that we put in the net yesterday - I don't know if it escaped or is just hiding well in the shells, but no site of it even after feeding cyclops. Best estimate as of this morning - 7 hatchlings: 1 dead, 1 MIA, 5 alive and well. Legs seems to still be doing well - waves her arms for some cyclops when we are feeding the hatchlings. I will try to go pick up a shrimp for her today.

Question about feeding the hatchlings - how much should we be feeding? We have been feeding 1 cube of cyclops per day, but I have NO IDEA if that is enough, too much, etc. I'm worried about the water quality now that we are feeding frozen food, but also want to make sure there is enough for them to eat well.

I also added another bottle of tigger pods yesterday.
04/28/15 -
Question about feeding the hatchlings - how much should we be feeding? We have been feeding 1 cube of cyclops per day, but I have NO IDEA if that is enough, too much, etc. I'm worried about the water quality now that we are feeding frozen food, but also want to make sure there is enough for them to eat well.

I wish I could give you a good answer but you are doing (and concerned with) is what I did - guess. Keeping the water quality high is a concern and small daily water changes are my best suggestion. If you are using carbon as part of your filtration, you might want to change it out more frequently or at least rinse it in new saltwater more frequently (I keep my carbon in mesh bags, rinsing weekly, swapping the bags each week so that this weeks bag is rinsed and soaks in RO/DI freshwater for a week before reuse. I replace the carbon roughly once every two months. There is no real technical reason for the timing.

They hide really well in the nets so keep watching for little arms :biggrin2:

:thumbsup: So far all sounds like it is going well!
04/29/15 - Just fed everyone one last time for today - it's amazing to me to watch the hatchlings appear when we begin to add some cyclops. This morning, like yesterday, we counted 5 hatchlings. When we fed them this afternoon we FINALLY saw the one we had put into the net - so that raised the count to 6 live hatchlings. Tonight we counted a 7, so we have split them into two groups: 3 in the net in shells and 4 on their own in the tank. They all seem to be doing well - we have covered the in-take slits for the filter with tulle and tonight it seemed like one was playing a game. It would float back toward the filter then swim away, then float back toward it again, until after a few rounds it tired of that and moved out of the way of the flow of the filter.

Yesterday I added another bottle of tigger pods and we added a harlequin serpent star and a couple of snails. We were pleased to see the hatchlings not be afraid of or bothered by the serpent star. They might be right next to the stars arms as it moves about, but the do not seem to mind each others company.

Legs seems to love for us to feed her some cyclops as well as a live shrimp when we have one. She will take the shrimp right out of our hands and eject the shell when she's finished eating, and she's taken to wrapping her "arms" around the pipette and holding onto it as we feed her the cyclops.

So far this whole experience has been completely fascinating!
Thank you for continuing to record your journey, it brings a huge smile for both your success and for remembering my own experiences with the hatchlings.

The fact that she is still eating is a positive sign for her longevity. It will be interesting to see if my thoughts of low egg rates = longer life holds true (It is so easy to generalize inappropriately with only a very, very few not well documented observations but Trapper lived on for another 12 weeks+ ). You will know her time will be over very soon (within 24~48 hours) when she leaves the den and wonders about the tank somewhat aimlessly. At that point there is a suggestion that a soft surface is more comfortable than the hard rock (guessing at the soft/hard - it could be warmth or even the absence of small clean up predators) and she would likely be happy to sit on your hand HOWEVER she is also likely not to want to leave and bite when you try to put her down (I have at least 4 octopus experiences with this - fortunately, no skin breaks but that may not hold up in the long run - infection is a very, very serious consideration). I am not sure what might be placed in the aquarium that would be equivalent (I have placed dying animals in a breeder net when I have observed bristle worms starting a bit early on their clean-up chores - really wish I did not have them) and if the octo would choose it. There are also good arguments for euthanasia at this point but I choose to try to allow nature to take its course in the most comfortable way I can think to offer. I suspect there is no right or wrong for the animal.
04/30/15 - This morning we were able to count 13 hatchlings! There seem to be a few who are either a little braver than the others, or more adventurous, or more active...I'm not sure why, but there seem to be a few who come out in the evening hours, but so far our biggest count is first thing in the morning - I'm usually checking and counting early in the 6:00 hour. We were amazed this morning and continue to wonder how many more there might be. Legs is still guarding quite a number of eggs many of which seem to have embryos.

With so many hatchlings we have increased the amount of cyclops we are feeding. For the first several days we only fed one cube, but with this many babies we fed closer to two today. We'll see how that's going at our next water quality check.

We added another bottle of tigger pods tonight as we don't see as many gathering at the corners of the tank near the sand which makes me wonder if they are begging to catch and eat those too?

We will update again when we have more news.
05/01/15 - We counted 17 hatchlings this morning and it is clear that some are newly hatched as they are noticeably smaller than some of the others. We are now feeding 1.5 - 2 cubes of cyclops/day. This whole experience is such a moment by moment roller coaster. It's amazing that you can see 17 hatchlings at one time early in the morning and then throughout the day not be able to locate/see a single one. In the evenings we usually see a few and go to bed wondering if the morning will bring them all back out, or if we will find that we have suffered mass casualties. I know that the natural progression of things will most likely bring about a serious drop in numbers, so I find myself anxiously awaking the morning hours to see where we stand.

I checked the water again today and everything checked out fine. We have started changing 2 stadium cups worth of water every day (or every other day when we forget) I assume the cups are around 32 ounces.

05/02/15 - The numbers continue to climb....this is day 8 since we saw that first hatchling and this morning I counted 21 loose in the tank and we suspect that there are still 2 in the net (only have seen one, but they stay incredibly hidden in the shells) - so it seems we have 23 at the moment. However, I have to say, they are getting harder and harder to count! They no longer seem to be content to sit in one place on the glass. They crawl, they "swim", they "float" from one place to another, they crawl around upside down on the plexiglass "lid" we have on the tank, and we watch them move easily through the piece of tulle that we have covering the intake slits to the filter - and then they come right back through when they are ready.

We tried feeding some thawed PE Mysis shrimp today but although some of the hatchlings came out to investigate, we didn't actually see any eating them. The serpent star was another story altogether - we saw just how quickly it can move once we added the mysis.

We added another bottle of tigger pods tonight - they seem to be disappearing quickly which makes me think the hatchlings are becoming more proficient hunters.
DWhatley - I just had the water checked and we have a slight (very slight) increase in nitrates and nitrites (I went to a different store today, so maybe they are the same as before but this person noticed?). She recommended adding some good bacteria to the tank?? Before I do, I'd like to get your opinion. Do you think this is a a safe option for the hatchlings?

I have one more question as well - given that we counted 23 hatchlings yesterday, do you think we should get our other bio cube octopus ready and move some over?

Thanks again for all of your time and input!!
Journaled experience is so limited (including my own) on raising mercatoris hatchlings that there is a lot of winging it. Mercs don't seem to be cannibalistic. There have been deaths with two unfamiliar adults placed together but not consumption and the general thought is that the death of one is unrelated to the other - but we don't know for sure. This is a guessing game. I kept mine in twos and threes as they grew but only had 5 to survive before space was an issue -- only 6 mercs in one case and only 5 survivors when there were ~ 50, the O. briareus were another story with only one surviving in each tank and cannibalism was a strong suspect.

Nitrates are not really worrisome but nitrites ARE (and are deadly). There are others that will disagree but I recommend getting some of the 5 in one test strips and testing frequently for nitrites rather than taking water to an LFS. Reagents are supposed to be more accurate but take a lot of time to use to test so the testing does not get done (my cross tests came out the same when I first started experimenting). Water changes and clean filters will be your best bet for handling the pollution. I would suggest doubling your daily water changes (you might do a larger one since you are showing a problem. If you are using carbon, I would swap in some new to be sure it is not adding to the pollution with captured waste). Adding bacteria won't hurt, there are a lot of questions about if it will help. The last study I read suggested it might be somewhat helpful to boost bacteria in a cycled tank (no so much so when cycling a tank) BUT finding live cultures is iffy.

If we assume you will have 5 or more survivors, then it is probably a good time to start up the other tank. I would use some (but not wholly) of your water change water and rock from the current tank to both quicken the cycle and to keep the parameters consistent. You won't have to move them for a month or more. I kept my first group in extra large breeder nets (about 3 x the size of the standard) for 5 months, grouped 2 and 3 to a net, GHolland used small tanks from the beginning (water changes become constant with small tanks - it worked but keeping the water quality is goosey).
05/04/15 - This morning I counted 25 hatchlings in the tank and I know there is at least one still in the net. We moved out most of the non-octopus friendly animals from our second bio-cube, sifted the sand to clean the debris and bought some live rock to add today in preparation for beginning to think about moving some hatchlings over in the next few weeks.

Although they seem to be thriving where they are, we noticed a big addition the last few days...there are LOTS of small, black, pellet-looking things littering the sand. They almost look like pencil shavings and we are assuming that it's the poo explosion that was bound to happen considering how many hatchlings there are and that they are growing well. We did our best to remove the poo, but I'm wondering just how we're going to keep on top of this since it's bound to be an on-going problem. Anyone have any recommendations??? I don't want to disrupt the hatchlings too much (here's hoping we didn't today), but there's no way that it's going to be good to just leave it in there.

We added 2 more bottles of tigger pods today - hoping to add enough that they can start populating the tank before the hatchlings eat them all or they find themselves sucked into the filter. Does anyone know of a way to tell if they are still in the tank besides looking for them in the corners near the sand? It will be nice when the octos are big enough that their food doesn't fit through the holes to the filter.

We continue to watch the occasional hatchling decide to take a trip into the filter, but we don't worry about it since we know they can come back out when they're ready.

Legs continues to eat. She will take cyclops from the pipette or a peppermint shrimp out of our hand. While there are considerably fewer eggs now than there were, there are definitely still some in there that clearly contain embryos. Today is the 10th day from when they hatching started. It will be interesting to see how many more days it continues.
5/10/15 - We are day 16 since we saw the first hatchling and Legs is STILL guarding and caring for more eggs! While it is VERY easy to see that most have hatched, it's hard to see how many are left. I could see 2 eggs still in her den tonight, but couldn't tell for sure if those are the last. I counted 30 hatchings on 5/7, but haven't gotten a great count since - they are so busy now that it's hard to get a good count. I do know that 4 have died - I'm sure there might be more, but those are the ones whose bodies we found. With the ones that have died (that we've found) it seems to be a case of wrong place/wrong time. The first one that hatched died, but that might have been due to us handling it too much (putting it in a glass to take a picture with a dime for comparison, etc.) or it could have just hatched too early. The other 3 have been found in unfortunate locations. One seemed like it might haven gotten caught between the plexiglass "octo-proofing" lid we have under the real lid of the biocube and the back of the tank, one was on top of the plexiglass lid, and one was on the ledge of the back of the tank where the filter is located. Those are the only ones we are sure of.

Legs was waving her tentacles like crazy tonight when I was feeding the cyclops so I blew some to her thinking she wanted some as well, but them I noticed she was definitely blowing it OUT of her den. I guess tonights waving was a "back-off!" not "me too, please!".

I think we've solved the poo issue as well. First - it seems that it's not onto poo, but rather turbo snail poo. We added some turbo snails on 5/3 to help with the algae that was growing all over the rocks due to leaving the red lights on 24/7 (we no longer leave them on all the time), and within 36 hours we noticed the poo - which makes sense considering just how fast they were removing the algae. We bought 12 feet of airline tubing from a local fish store and it is the perfect solution for removing the poo without removing too much sand or water. The tubing is less that a pencil eraser in diameter and does a great job of sucking up the yuck.

Here are a couple updated pictures of the hatchlings.


5/15/15 - The hatching is complete. Legs still stays in her den, but there are no more eggs. I tried to feed her a shrimp today - at first she seemed to move slower than before and not have as strong of a grip, but she eventually took the shrimp and pulled it into her den. Unfortunately, it wiggled loose and swam away. She does seem to still be eating some of the cyclops and mini mysis, but it's hard to say for sure.

We tried feeding some frozen mini mysis today in addition to the cyclops and some of the hatchlings seem to be eating it! A few seem to understand that the pipette = food and they will occasionally come right up to it when we're feeding them. It's a little more difficult with the mini mysis because they get stuck in the pipette and if we squeeze it enough to blow it out, the hatchlings sometimes get blown a bit too.

I counted 23 hatchlings this morning, but I found 4 dead today, which with the couple that I found yesterday brings the known total to 10. I know it's to be expected, but it still stinks. The ones we have found seem to be quite small, so I'm wondering if they were the last hatchlings to emerge. In spite of having pieces of tulle covering the slits that allow the water to flow into the filter, the hatchlings still crawl through. We have watched them crawl through and back and have decided that there is really no way to prevent it. Yesterday I counted 11 back there! I managed to move 4 back into the tank, but the other 6 were unreachable/uncatchable. However - there are a good size, so it does not seem to be harming them. I have seen two ooze through the cover into where the balls are in the filter, but there's really no way to know if they are still there or still alive. When I count the hatchlings I just count the ones that I can see at that given moment.

Our second bio-cube is almost ready for us to be able to move some over if/when the time comes. I did move 2 of the emerald crabs out of the octo tank and am planning to move the other 2 as soon as we can catch them. We will still have the turbo snails and serpent star, but one of the crabs tried to grab a hatchling today. I can't say for sure if it was intentional, but it doesn't matter - the algae is gone and I'm concerned that they may tried to grab the hatchlings if there is not enough algae to keep them busy. We have gone back to keeping the red light on at all times and just turning the regular lights on for a portion of the daytime.

Here is a photo of one of the hatchlings that we lost. It is amazing to me that there can be so much detail in it's tiny body.

The octos that we (the collective hobbyist we but applies to professional biologists and public aquariums in general) have been able to raise are all fully formed at hatching and live on the substrate within a day or two of hatching. The small egg species have a planktonic stage and their arms (and likely other parts) are not fully formed when they hatch. Once all their parts are complete, they become benthic and leave the water column (like squid, there are midwater species but these we only see in videos from the science community or oil rigs).

Keeping my :fingerscrossed: for a continued great adventure!
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