Gravesly,
Forgive my ignorance (can I claim being female here ... nahh. True but not an excuse). I looked for Neal's plastic thingy with the gauge holes for sizing but he obviously used it last so it is not where it should be
but if my not so spacially inclined memory serves, you went to smaller rather than larger after your second look. Additionally, I am assuming that even 16 gauge is smaller than .5 inch.
If my poor concept of sizing is correct, I am afraid I have sad news
and expect that you have what is known as a small egg species octopus. Raising these little plankton size critters has proven to be all but impossible in an aquarium (both home and professional). Give it a try, of course, and you might try feeding rotifers, some (but NOT solely) new hatch (less than 4 hours hatched) brine and cyclopese (all the same time). You will have problems keeping the water clean enough and enough gentle movement but what the other reasons for failure are I can't say (the ones I mention I am aware of for baby seahorses). As difficult as it would be you might try culling them to a managable size or at least removing 5 or 6 and putting them in their own tank for special attention.
I have kept Trapper alive for 8 weeks beyond hatching (she is a large egg species and likely has other differences as well) with the following regime:
When she refused live crabs dangled on an air tube, I froze the crab the night before, thawed it in cold salt water and offered it on the air line tube.
When she began refusing dead crab on a tube, I offered it by hand.
When she began refusing hand fed crab, I offerred recently killed (immediate) shore shrimp injected with a solution of Tetracycline.
When she began refusing shrimp I started feeding cyclopese and this is where I am now.
The cyclopese is difficult to feed since it is very small and frozen. I put a small block of it in a shell directly in front of her den an let it settle and thaw. It makes a mess in the tank and raises the nitrates (no ammonia or nitrite detected). I cut my recirculating pump off at night (she is nocturnal) and only leave the primary pump on (which does eventually move the cyclopese to the sump) and then allow the secondary recirculating pump to run during the day (I have it on the same timer as the lights - it causes too much movement to attempt feeding the cyclopese).
I cannot say that this series of feeding methods has anything to do with her somewhat extended life (it may be natural) but I am hoping others will try some or parts of the method and report. Basically what I observed is that she regressed in her choice (or ability) of foods back to baby food (not unlike humans
). I only tried the cyclopese because I noticed her flailing arms everytime I fed the babies (they are in a net breeder in the same tank) and eventually realized she was filter feeding just like the little guys. When I put the cyclopese in the tank she grabs my fingers with two of her arms but I can't get her to take the frozen cube directly.
Good luck and keep posting what you discover.