light bulb for m/h

[steve.bridges]

i have a m/h pendant light with a 250w hqi 10000k, i was wondering if any body knew if they do higher K like 14000k, would this be a better option for corals. I like actinic effect and am wondering wether this would be more like it. The 10000K is yellowish and may be increasing my algae population.

i have about 15 corals brains leathers xenia gspolyps. Tons of critters, a tomato clown, wrasse, damsel and firefish, Not the prettiest bunch but ive grown fond of them and cannot move them

thanx guys, any help is always appreciated.

[this is me]

yeah, 10k is a little on the yellow side as well but corals grow quicker on the 10k.
Myabe you sould supplement it with some actinics?
I have the geisman 13k megachrome and they're white with a hint of blue. I'll try out the Aquaconnect 14k(I heard you cant find any in the states) once its available and when my 13k is out of life.
here a pics of my 13k megachrome with an e-balast.
I know its hard to tell from picture but this is pretty close to what it really looks like in real life
http://www.acurainspired.com/gallery/data/19f3cd308f1455b3fa09a282e0d496f4/full_840_p28491.jpeg

[greenbean36191]

If you want an actinic effect go for 20ks. Your corals should have better colors if everything else in the tank is good, but they might grow slower.

[this is me]

I heard 20k gives alot of heat as well. +2 degree?

[Doug]

Originally posted by this is me
I heard 20k gives alot of heat as well. +2 degree?

Color tempature of the bulb does not cause more heat. The wattage output of the bulb is the largest determining factor on how hot the bulb gets.

[Frick-n-Frags]

regarding actual actinic light frequency output, the 10kK HQI's put out more 420nm than any other bulb available (as per Sanjay tests) even though they have a more white balanced overall spectrum. Iwasakis put out a ton of actual actinic too. That's why corals grow better under the "white" lights as much of that pretty blue light is not actinic, just pretty to look at.

The wattage consumption of the whole bulb/ballast rig WRT how much actual PAR is produced determines how much heat is produced.
Lower PAR bulbs(ie typically blue bulbs) waste more wattage as heat than the more efficient white lights if the power consumption is equal. If the juice isn't used for making light, it is used for making heat.