Just reading about your inking incident!!! Funny all the octos seem to be different on this. Now, Ink used to ink quite a bit when she was younger. Same type. Very mucasy! Now G2 for a few months there would ink probably every couple days and the amount in the tank would make it have a cloudy haze for a few hours. Never seemed to affect him at all, as well as the resident shrimp in the tank. He would just startle if myself or Jess approached the tank too fast. Now, I have to admit, I do causiously approach the tank, till I am sure he knows I'm there. He does still startle alittle like he's going to jet away, but the inking has subsided.
Also, G2's colors are amazing. When he's hunting he can be a dark chocolate brown. When he's sitting watching me, he gets totally textured and can change from a light color to a sort of zebra pattern. When he's sleeping, he's the blueish color you mentioned. Maybe yours was asleep and thats why he startle and inked!
Glad to hear he's doing so well!!!
Carol