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i had a post similar to this a lil ways back.... i put just actinic in and my octo never came out. it looked cool to see in the tank and i thought it would be a light with less strength but from what i hear the octopus's eyes see that light different than we do. it is much brighter to them therefor they stay in the den. once i pout my 10000k daylight back in there and ditched the actinic i cant keep the lil guy in its den!
Abdopus is a day active species that tolerates very bright light, probably because it lives in the very low intertidal to just subtidal. O. cyanea is another species that is also day active and doesn't seem to mind bright illumination.