How many K should the bulbs have?

[Lemeshianos]

I will be going to pick a MH bulb for my light fixture. It should be a 150Watt bulb and I was wondering how many K are needed for corals. If I am not wrong 10,000K are suitable for coral growth and then you go higher if you want a more bluish color. To be honest I'm not very keen with the bluish look I see in most pictures.

The light fixture also has 2 actinics so I will be getting some blue effect from them.
Do you suggest a 10,000K lamp or a 14,000K bulb?

Also what can be kept under:
1x 150Watt MH
2x 24Watt actinics

My aquarium is a bowfront 75gallon and the water depth/height is about 22-24 inches. Could I keep LPS right under the MH light and softies around it where the light is not that intense?

And are 150Watt enough for an anemone(after about a year when the tank matures)?

[Palting]

IIRC, 10k is white and looks good to human eyes, 20K is blue and improves growth, 14-15K is the compromise. 150W should be OK up to 22"-24". For my 150 gal with 24" depth, I am using 3 150W MH plus 8 T5 actinics.

[Paco]

IIRC, 10k is white and looks good to human eyes, 20K is blue and improves growth, 14-15K is the compromise. 150W should be OK up to 22"-24". For my 150 gal with 24" depth, I am using 3 150W MH plus 8 T5 actinics.

You have it backwards -- the lower "color temperature" usually promotes best growth -- Iwasaki 6500k are great for growth but look terrible. Higher number = more blue = more florescence and prettier.

A 150w MH in a 22" deep tank isn't ideal but you'll be able to grow SPS in the top half of the tank assuming you have good reflectors.

[Lemeshianos]

So if I supplement a 6500K with 2 actinics will that achieve a good color and florescence or is it a better combination to use a 10,000K with the actinics.

What are actinics actually good for?

[bnumair]

i would use a 14k bulb. reason for that is that u will lose 10% every month.
if u start with a 10k bulk it will be bright and good for growth but sooner it will fade and will he great for algae growth. 14k bulb will last a bit longer.
the other post here has it wrong. 10k is bright white and is good for growth.
20k is blueish more for display and bringing out color of ur corals.
12k and 14k are in between shades for people that wanna have both effects of 10 and 20k bulbs.
hope that helps

[shifty51008]

6500k is gonna be a very yellow color I would just use a 10k bulb if you like the crisp white look. the actinics give the look of deper water and also makes the colors pop more in the fish and coral.

for me I like a bluish tank so I run XM 20k's with vho super atanics and even though it isn't really blue I like the color alot

[MCary]

The higher K's have a more natural look. Blue wavelengths penetrate deeper than the red wavelengths. Its why the sky is blue and its blue under the ocean. The red is filtered out.

I start with 10K and usually don't go higher than 14k. I get fantastic color development on my sps with 10K, 20k is too blue for me and somewhat unnatural. Although I've never used it, I've seen it on others.

5000-6500 is a full spectrum bulb and great for growing plants. Unfortunately, it is also great for growing algae. I personally wouldn't use them.

But that is just my opinion, I could be wrong.

[cdeboard]

yeah id recommend a 14k bulb with actinics.... will look perfect. 10k to me is kind of yellowish quickly. I just switched up to 20ks yesterday for that more blue look.

[Palting]

Yeah, my bad on my last post. Here's a link to help all understand MH and color: http://www.reefkeeping.com/issues/2002-08/dw/index.php