how long b4 replacing MH bulbs?

[killyah]

so how long do MH bulb last? a year or more? (Iwasaki 6500k 400 watt) (Radium 20000k 400 watt)
i know vho's should be replaced at least every 6 months... but some keeps them longer.
also would 2 400 watt MH be good enuff lighting for a 125 gal tank? i wanna keep soft and hard corals, maybe clams..
i cant seem to make up my mind on lighting thats why im asking, im either going MH or vho's. not both, cost wise is the reason what do you guys say?

 

[infinsable]

They should be replaced once a year,even if they still work the spectrum is lost

 

[killyah]

thx guys. but also i would like to know would 2 400 watt MH be good enuff lighting for a 125 gal tank? i wanna keep soft and hard corals, maybe clams..

 

[adrian]

You shouldnt have a problem keeping most corals ruuning 2 400 MH. As you can see above the life of a MH bulb really depends on what bulb you use. HTH

 

[wamp]

I run mine for one year, or until I decide to try another bulb. VHO once a year.

 

[jonthefb]

On my 125 i have 2 175 watt MH and 1 400 watt MH, and two actinic vho's and i am growing hard and soft corals and clams like crazy. I think you will be fine. this thread reminds me that i need to change my bulbs. Its been about a year and time to dish out more moola. I just changed the two 65 watt PC's on my 20 gallon, and man what a difference. i dont know what kinda white bulb i was using beore but got a 10 K white and one blue actinic, and man the colors of my corals were totally recharged!. IT looks like a totally different tank.!
good luck all!
jon