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A Couple of LIGHTING questions


Jul 11, 2003
I have two lights that are each 55 wats each, and I was wondering how many wats should they be?

Also, right now my light turn on at 12:00 a.m and turn off at 8: p.m. Would there be any adverse effects if I were to turn it on for longer like say maybe 9 a.m to 9 or 8 pm?

thanks everyone

p.s- one of the lights gives off a blueish glow and the other one is normal.
For a bimac this might be okay, as they are mainly diurnal but the light may caue other species to hide... might be better just using one of the tubes when you get the octopus for the first month or so.

I have normally given cephs a 12hr photoperiod or thereabouts and i set it for when i am in the house... EG my tank just now has a timer with lights that come on at 12pm and off at 12am....

The bluish tinge is common in tanks for SW as blue light penetrates water to a greater depth than red light does... checkyour bulbs, the blue one may be a different Kelvin... probably say something like 10000k
You can expect an alage bloom if you change the timing in your tanks lights in a new tank.. so maybe just increase it an hour at a time over a couple of weeks to prevent that :)
I think this question has already been answering, but I still dont know the answer to it. So, i apologize for asking but how many wats exactly should power an octo aquarium? Like i said right now alltogether i have 110 wats of power.

p.s- my tank is around 84 degrees, so im hoping that a lights of lower intensity will cool it down a couple degrees.

thanks in advanced
Flourescent bulbs don't really give off too much heat, and the Kelvin ratings are more geared towards the coatings inside the bulbs for specialized purposes, so the amount of heat from the bulb won't really change from type to type...you should be fine either way!
I like to vary my schedule with the local sunup/sundown...shorter hours in the winter, and longer in the summer. Heck, nature can't be too far off her rocker! :)
thanks cthulhu,

So how many watts should it be?? Are u sure they dont give off much heat. My cover glass is burning up when I clean it, and when i simply put my hand under the light i can feel the intense heat.
Amounts of heat are...relative. What kind of lights do you have? You mention two at 55 watts each. That sounds like two Power Compact fluorescents to me. Are they relatively small, short, and each one made up of a double tube?

My lighting keeps my tank temp 10 degrees or so above ambient temp, so don't be too surprised at the heat you're feeling. Your tank would be cooking if you were using incandescents to provide the same amount of light.

As for amount of light good for an octo...well, I'm not totally sure myself, but more than you have wouldn't be ideal. I'm guessing you probably have just about the right amount. They don't NEED light, specifically, except to help them see and to establish a normal, comfortable, routine environment for them.

Im not exactly sure what kind of lights they are but here are some pics. I just think htey might be to bright because whenever i watch the videos and such on this site everyone elses tank seems so much darker than mine, and my temp is pretty high :cry:
Those are power compact UV lights...meant for reef systems! I would use only one bulb on the tank for octos (the daylight, not the actinic)...or just get a regular flourescent fixture...those pc's will overlight the tank!
haha i thought they were to bright :lol:.

I took the blue one (actinic) out, and i must say it makes the tank look alot less attractive, but if it is what is best its a small if any sacrifice.
or just get a regular flourescent fixture....

what exactly do you mean by that?

thanks a bunch for all your help.
Hi Rockthis,
I was just looking at your tank parameters on the Octo Database. Is your temperature still 82 degrees? If it is, you need to bring that down before you get a bimac. Maybe the lights are contributing a lot of heat. So let us know what your temperature is, then maybe we can help.

yes it is still 82 :cry: :cry: :cry: :cry: :cry: . I am hoping that the lights are a relatively big part of this heat. Right now it is summer so i am also hoping that as things cool down so will my tank. I dont have a sump so the swamp cooling method wont really work ( a fan wont fit on top of the tank). So i am really stressing about this temperature thing (maybe i will ink :P )

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