MH lighting spectrum

[jnguyen4007]

I'm getting ready to look for a replacement MH bulb and I see different type that said 10K, 15K and 20K. Can someone tell me what's the difference in these spectrum and how it would affect the way the tank look and the possibility the growth of the coral? Also, does higher spectrum means shorter bulb lifespan?

 

James

[djcerna]

10,000K = white light, 15,000K= light blue and 20,000 K=blue

Coral grow faster with 6500K or 10,000 K but most people don't like the look of the washed out color of just the 10,000K. They usually add antinics to add more blue and florescence.

The bluer the color the slower the growth usually. Chose the color that works for you.

david

[jason the filter freak]

Ask to borrow old light bulbs from other members to test out the color in your set up.

[lanman]

14K is kind of 'middle of the road' on both growth and color. One of the reasons I like T5's - I have bulbs covering the whole spectrum in there. Main reason I like MH - it has 'sparkle', and reflects off of water movement - and makes pretty lights on the ceiling.

 

And just off the cuff - I have determined after 6 months, that 70W MH is really not quite enough for a 24-gallon reef tank. The only place SPS grows well is up very high in the tank. I think maybe 70W MH over an 18-gallon tank would be about perfect.

 

bob

[dschflier]

jnugeyn If you want you can use some old XM 10k 250 watt SE bulbs I have. LMK if you are interested. I am not sure of your wattage and if you are using single or double ended but I have the SE 250 watt XMs