I got an Atlantic pigmy octopus about a month ago. All was well within the last week or so he has rejected all food. Today he was out on the glass

[Btay4554]

I got an Atlantic pigmy octopus about a month ago all was well. Within the last week or so he has rejected all food. Today he was out on the glass which was a little worrying as he is nocturnal. I also noticed there is a few chunks missing from his tentacles.
He is currently housed in a 10 gallon aio system that has been up for roughly 3 months before the octopus was introduced. I’m pulling water from my established established reef and doing water changes weekly.

 

[tonmo]

Sorry you're dealing with this @Btay4554 -- even though pygmy octos can do well in smaller tanks, 10g may be far too small. I'm not 100% sure, but I think the smallest advisable tank for an octo is 25g? We can both have a look at this using the Search feature.

Pics may help also -- are there any tankmates, or are the arm injuries from autophagy, or something else?

 

[pkilian]

Its hard to diagnose the real issue without more info. Do you have any photos of the tank setup and the animal? Also, what has your water quality been like recently? Ammonia and Nitrite levels?

Your animal may also be getting older and beginning a normal senescent process that happens to all octopus as they begin to die. Do you know how long ago it was collected?