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Light Opinion


Aug 3, 2007
Ok, I know there is alot on the use of red lights for Octo viewing and moon lights are bad. I just got a 3 part light and wanted some opinions:

The 3 lights are Daylight, 4 blue leds, and ACTINICS. (the last I dont know what that even means)lol

Anyway, Kenny seems to come out and like the 4 leds the most but I will post all 3 views of my tank to show the lighting differences...BTW, the pink to the left it where the light is going through my plexiglass that I covered with red celophane.
Please let me know what you think!!! Thanks!


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The actinics are the blue spectrum. They are going to appear the brightest to your octopus from what I understand. The role they generally play in reef lighting is making the corals fluoresce.
Animal Mother;104141 said:
The actinics are the blue spectrum. They are going to appear the brightest to your octopus from what I understand. The role they generally play in reef lighting is making the corals fluoresce.

They also peak in a good range for photosynthesis.
You might want to go with ambient for the first week (or two) until Kenny adjusts to his new home and you have a good feel for his behavior and active times. I would then try the artificial lighting that most closely matches his most active periods for your desired observation/feeding time unless he stays active only at night. I leave my red light on 24/7 with the nocturnals and use LED's for day on one tank and ambient (many windows) for the other. The reduced lighting makes my octo tanks a window cleaning joy compared to the reefs.
Thanks for the info everyone--now, what about the red film I use on the plexiglass between the light and the water? Does that help or change the spectrum that he sees it? Oh, and the blue leds- I know the blue is bright for him but you also can see how dim they are--should I still be concerned?
ps, I am putting an update in the Kenny journal--he came out in the night and created a small "nest" as best I can describe it in the corner on the sand!!
I use a red film on my tank light (all of it, not a portion) and it works very well but for the next couple of weeks you may want to create a normal day night cycle to determine if Kenny is naturally nocturnal or just adjusting (Vulgaris and Briarius are supposed to be early morning and early evening active by nature so there may be others with the same natural schedule). If he turns out to be diurnal, you will not need the red lighting at all.

Blue lights may, however, be a problem. Dr. Jean :wink2: has reported serious negative and anti-social behavior in the large New Zeland octos but how applicable this is to others has not been reported any time recently. Most of us avoid the blue as time is so short with these as pets. Next time a grad student writes in wanting ideas for an experiment I hope one of us makes lighting study as a suggestion (we need a string around the finger smiley). There is at least one article on-line that mentions that octopuses can see light in spectum we do not but the study was done by disection rather than reaction observation.
i have a 4bulb t5 unit,. i run with only two bulbs, one full spectrum and one actinics, my octo only comes out at night so i run it for my zoa's. i have left it off for two days but he never came out in the day so i run it 10 on 14 off.. i figure a reef octo is use to sun light, they dont like it they hide like they do in nature.. no harm in that i wouldnt think.

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