Week 4, and not a very good one ... Omikron has become quite shy again and is hiding for the better part of the day. We even have trouble finding her for feeding, so she missed a couple of meals (but seems to be compensating on this with the last few shrimp still in the tank). There was one night in the beginning of the week when, due to electrical problems, the lighting cycle was delayed; but could this irritate her for more than a one or two days? So for now, we sit in front of a tank mostly without seeing anything.
But whe she finally appears, mostly attracted by thawed shrimp (still her favourite food), she looks good, moves around smoothly, shows different colours etc...
We are a bit undecided about how to deal with her food - should we say, as long as she does not appear, obviously she's not hungry, or should we poke around to find her and feed her?
I can't give a good answer, unfortunately. Routine eating is always preferred but schedules vary widely among keepers. You might try feeding only every other day to see if she actively comes to feed on schedule. You can also try reducing the size of the food and continue to offer daily goodies. I would recommend not keeping more than a meal's worth of live food in the tank though as it may be part of what is making her shy.
Omikron is in the tank for two months now and has settled in well (again). She lost most of her shyness, esp. towards new faces who appear outside the tank, and is (for most of the time) an interactive and playful cephalopod.
What she really hasn't figured out is a day/night rhythm. Sometimes in the morning, when the light goes on, she'll be awake and ready for feeding, and again in the afternoon when we come home. Sometimes we won't see her during daytime for two days, but in the night there is a shadow gliding through a dark tank (very mysterious, yes, but somewhat dissatisfying).
Her missing arm has been growing back to almost full extent, but it's still thinner than the other ones.
she has clear preferences whose "taste" she likes or dislikes ... the latter is me, unfortunately. Interestingly, people who smoke or are on medication seem not to irritate her at all. I suspect it's a male/female thing ...?
lately, Omikron has been acted strangely and was very reclusive again. Water tests did not inidicate anything, but as her behaviour kept on for several days, we had the water tested at the store, and it turns out that phosphate is significantly elevated (we tested this at home, but our test didn't say anything ... a different test we purchased now does). The test recommends <0,02mg/l, while it now indicates about 0,2mg/l. So well, really high. But then, the problem seems to be algae and corals, and not really anything that bothers the octopus - ? Could this affect her behaviour? And now ... should we panic, really try to replace as much water as possible and add a second filter to the tank filled with phosphate blocker? Or just calmly do some water changes and add the blocker to our normal filter system?
We have no evidence that phosphates (or nitrates) are a significant problem to octopuses. I would consider doing multiple water changes in a week (because of the behavior change) but NOT excessive amounts in one change as we do have evidence that parameter fluctuations (salt and ph) are negative impactive.