400 watt metal halide on a 100g

[WyldFya]

Wouldn't most fish be spooked/washed out from all that light?? I used to grow with a MH400 and they are retarded bright. Wouldnt 2 175's be better? But you can only get 400's right?CFL's throw some major light too,and if you get a drop of water on the buld they won't impolde violently like a MH.And there WAAAAY cheaper.

Compact fluorescent lights are far weaker in lumens, and their penetration power is next to none.

 

[Unxpekted]

I run 2 400's on my 125, got the whole setup from a closet horticulturalist..... I do find the light a little yellow, but to be honest I havent even checked the K rating on the bulbs so thats probably it. I know when I had my snakehead in it the plants grew like wildfire, but now that.....its......a......community.....
tank.....(Lost my snakehead when I moved a little while ago =/) and I have alot of surface disruption via bubbles, everything seems to have slowed waaaay down. Id definately recommend a CO2 system of some sort, that much light is wasted without it. Good luck =)

EDIT: Also, even with my snakehead splashing around in the tank, I never lost a bulb. They are covered in splash marks, but never popped. Just lucky maybe, but I thought Id throw that out there.

 

[HunterX]

Yeah, I agree - go with a tank if you're going to do Co2. Yeast/sugar method is inconsistant, a pain to keep up, usually inadequate , and ends up costing more in the long run.

 

[C J Castle]

You need CO2, heavy planting and a dosing regime withthat much light; otherwise, algae blooms will be very big issues!

 

[lemcc]

i think its too much light
1st what are the dimensions of the tank
MH's are great if you need them (if you don’t you will not be happy with it)
HOT/color fades very quick/HOT/can be dangerous if not installed properly/HOT
if your tank is less than 30" tall you don’t need it IMO
with the cost of operating it and bulb replacement the extra cost of PC's or T5's would save you the difference quickly
remember in planted tanks light is the gas pedal

 

[ewurm]

If I had a 400W metal halide, it would be SW. I think that is a bit on the high side for planted unless you follow the recommendations stated before.