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atintic or no?

Mar 21, 2007
my octopus seems like it wants to come out during the day but the light is to bright so it waits untill the second the light is turned off. i recently tried removing the 10,000k daylight and keeping my actinic in and he seems to like it better. i just got done reading a tread and it said that actinic is to bright. I'm not worried about the brightness because my octo seems to like it better, i want to know any other suggestions because i do not like the look of a blue/purple tank...i have a 4' double bulb fixture that uses t5 bulbs. if anyone has any idea of a bulb a should try please feel free to post. thanks!


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This is all theoretical, so going by what other octo-keepers have observed may be more useful, but I think this info has helped a few folks get some more viewing of their nocturnal octos:

For the most part, octos don't like bright light at all... Although blue light is closest to what they'd see in their natural environments, even the species that aren't nocturnal are usually more active at dawn and dusk than the brightest part of the day. Also, an octopuses eyes are sensitive to different color ranges than ours are, so they see blue light as brighter than we do, and red light as much dimmer, and maybe not at all. If you're interested in watching while your octopus is most comfortable, increasing the red light and decreasing the blue will be the best tradeoff for making the light seem dim to your octo while still allowing you to see it. Some people have had some luck with using red LED flashlights in an otherwise dark room... LEDs in particular are probably good for this, since red light bulbs are white or yellow with a red filter, so they sometimes seem to appear bright to an octo. There are apparently also "Red UV lights," which is actually impossible (UV is bluer-than-blue, so it can't be red) which probably are UV lights tuned to make some corals and things glow red... I'd expect those to also look bright to an octo.
thanks monty, your been a good source to me directly since ive had the experience of this octo. i was just going by my eye and seeing that the blue made it look darker but i noticed that my octo is just as happy with the 10000k daylight being that they are the only 2 i have without purchasing another bulb. im going to go look for something with more of a red in it but this will work for the mean time. i have to say this is one of the coolest things ive ever cared for. ive had anything and everything you could name in fresh water, ive had a saltwater fish tank, a coral reef, a few stingray's (which was pretty cool) and now this, i have to say you get the most contact and the coolest experiences with octos. its been a few days now and its happy enough to come to my hand whenever i put my hand in the water, and something else that seems to me would make others jealous...its eats everything ive thrown to it meaning fresh/frozen/ or live:biggrin2: well i just want to say thats for the fast reply and i look forward to talking again!
Jean recently suggested ( is my tank a good home? ) that actinics are annoying to at least one of the octos they kept:

"Greg, I suggested pulling the actinic, our octopus HATE them we had one that used to target them with a blast of water, which would've been OK except that it was an old system and the water tended to destroy the bulb and blow the breakers for that side of the aquarium. We've since upgraded so that can't happen, but we leave the actinic off in the octopus tank! "

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