Which spectrum is most beneficial for photosynthic inverts?

[travisurfer]

Ok, I want to know which spectrum is the best for coral growth. Putting aesthetics aside, I want to know which spectrum will give you the best growth.

[Amphiprion]

I didn't vote because it depends upon the depth in which particular types of corals reside. Some have little "blue" in the spectrum, while other have quite a lot.

[travisurfer]

so, for deeper water species, more blue light is required due to the water absorbing the spectrum, while a lower spectrum like 6500-1000k would be better for shallower corals because it has a fuller spectrum more like the corals natural lighting scheme? while i know this to be true, i want to know the general spectrum that will allow most corals to thrive. i was going to be using a standard 50/50 bulb; however, after reading a thread over on www.nano-reef.com and some things i remembered from wetwebmedia it seemed more like the 6500k was the preferred spectrum for corals.

[Nano_reeflover]

I think you need to ad another ''0'' to every number above 8800k

[travisurfer]

wow, stupid mistake. as long as everybody knows im really talking about:
6500k
8800k
10000k
14000k
20000k

[travisurfer]

ill either be getting the: Sunpaq 6500k/10000k
or
Hellolights 10000k
for my 65w single strip pc

[travisurfer]

can you help me decide between the standard 50/50 or a 10000k bulb for my tank. i am leaning towards the 10000k b/c it has a higher output of usable spectrum and i dont have the strongest lighting.

[travisurfer]

anyone? im getting some votes that are helping me out but i just cant seem to decide which bulb. sunpaq also makes a 6500k/10000k

[jeffbrig]

Keep in mind, the numbers assigned to bulbs are usually assigned as marketing devices. Not all 10k bulbs are the same, nor are 14k or 20k. Some 14k's "look" bluer than another brand's 20k.

What is significantly more important is to look at the spectrum output of a given bulb, and compare levels at the wavelengths that organisms in your tank use (~430nm, ~670nm). These levels can be independent of the perceived color of the light, which is a function of all wavelengths generated by the bulb whether they are of use to your photosynthetic organisms or not.

I'm sure that's not what you wanted to hear. :D

[travisurfer]

Haha, thanks. Im just trying to decide between these 3 bulbs so i can order one tonight. that way ill be able to start my tank up sooner.

[vessxpress1]

I've got 2 96 watt sunpaqs on my tank. I believe they actually sell 6700k bulbs not 6500k if I remember right. Not a big deal. I was wondering the same thing you were. My fixture came with a 10,000k bulb and a 420 nm actinic. The actinic by itself made things pretty extreme blue. It was a lot. I didn't know what to get so I just decided to mix it up and try to have the best of everything once I discovered the sunpaqs.

I ended up getting the dual daylight 10,000k/6,700 k bulb and the 10,000k/ 460 actinic bulb. So I still had the equivalent of a full 10,000 K bulb worth of the daylight, but just mixed in the extra 6700 k. I love the half and half bulbs. It did give the tank a more yellower, shallower look. I've only had them for a little over a month so I can't say I've had an explosion of growth yet, but they seem to work well, and i"m happier knowing I have a better mix now, whether it's doing anything more or not. I'll probably replace them with the same ones again.

These sunpaqs were a lot better than what came with the fixture. They're suppose to be some of the best PCs you can get. I'm happy with mine.

[travisurfer]

That is why I was considering the dual daylight from them. It seems like it could be a little yellow so thats why I was considering the 10000k bulb from hellolights. What do you think?

[vessxpress1]

I was concerned about it being a little yellow at first too, but I'm happy with it. Granted, I'm not a light 'conesour' so some people here might tell you they hate it.

I think it's a personal preference and you probably won't be able to notice the difference in coral growth unless you have things that are really fast growing, or wanted to set up a time lapse camera on it for a few months and then try something else. My problem is, I see the tank every day so I really don't notice growth that much, but I know it's taken place. For example, all those xenia you saw around my BTA with that maroon clown....those have all grown in the tank since mid November. I didn't put them there. I actually took the original cluster back to the LFS for an in-store credit and got the maroon clown. :)

But getting back to your situation, don't sweat it too much. You're only going to have the bulb for what, a year, 14 months max? Then you need to buy new ones anyway because the spectrum's gone, but obviously keep them around for an emergency.
If you don't like what you get now, just use them for a year and get something else next year, or get both.

[travisurfer]

ok, thanks. i see my tank everyday too. i think ill be going with the sunpaq dual daylight to max my fixture's output. if i dont like it first, ill always get used to it; or upgrade eventually.