question about metal halide bulbs

[ENraged]

question about metal halide bulbs:
I have been thinking long and hard about what would make my corals look the best and was wondering this.
If i did get a 70 watt retrofit in my hood (modded to deal with heat) with the 1400k astralux bulb would the stock Actinic bulbs still be needed?
If i could gut the stock lighting completely out and have only the mh retro, fans, and the heat shield cooling would be much easier.
Would loosing the dawn/dusk effect be awful for the health of my corals?

any advice would be greatly appreciated

 

[louist]

Actinic is mostly for aethetic purposes and for dawn/dusk effect. If you need to remove it to get the MH retro in, go for it. I must admit that corals look quite cool under actinic.

I don't have actnic on my tank, and everyone/everything look just fine.

 

[ENraged]

from what i was reading the 20k bulbs have a nice blue spectrum

 

[Pattylucylaura]

Yeah they do but you have to go high wattage to still get good growth in a 12 gal it might not matter. The 14k's give off a nice blue spectrum also.

 

[ENraged]

<a href=showthread.php?s=&postid=7728405#post7728405 target=_blank>Originally posted</a> by Pattylucylaura
Yeah they do but you have to go high wattage to still get good growth in a 12 gal it might not matter. The 14k's give off a nice blue spectrum also.

So you feel 70 watts over a 12 gallon tank with a water depth of around 11 inches might not be enough?

 

[Pattylucylaura]

No 70w is probably fine (I personally would go with a 150 just because I like to fry me eyes. ) what I was saying the bluer you go the lower the intensity of the bulb take this for example a 400w 20k would be like haveing a 250w 14k or a 175w 10k you need the extra power to be able to get the intensity when you go higher up on the spectrum. Does that make a little more sense. In a 12 gal with a lower water collum you will still have a lot of intensity with a 20k bulb but you might not see the growth you would if you were to go with a 14k or 10k bulb.

 

[ENraged]

ok thanks.
Anyone else have any opinions on the subject?
Think i am going to stick with the 70 watt 14k set up as i only want to keep one or 2 sps and clam in the tank.
I can place those high in the tank to get more light