400 Watt metal halide on 75 reef

I have just received two free 400 watt metal halide fixtures i am building a 75 gallon reef that i want to be able to put any thing my (wifes) heart desires in will one be enough lighting or should i consider using both of them or will that be too much?
thanks in advance

 

i'd only use one, the only problem I see is the light coverage. Personally I would sell these and get 250's.

 

250s were my original intent but i wanted to see what others thought before i made any final plans free has a nice ring to it but if it will not work as well as 250's i will go that route

 

I run three 250 watt HQI MH and four 96 watt PC's on my 180. I agree - sell the 400 fixtures and buy 250. You could use just one of them but you will have a bright spot and I am betting you would be happier with 2 fixtures.

 

It will probably burn a lot of corals.... You may be able to place things far away from the light or deep, but sounds like too much light.

 

one bulb covers approximately 2x2' area, i have 2-400w mh on my 75 with acropora. what corals are you going to house?

 

i'm not sure at this point i am trying to go with a reef i think i want a carpet anenome and a lot of variety probably some soft and hard corals but im new to all this so i want to be able to add what i want without having to upgrade lighting again. I just want to make sure i do things right this second go around and fix lighting issues local fish store (now out of business) didnt know about when they sold me my current setup.

 

If you're going to have a general assortment of corals.. I think Crimson said it best above.

I'm not planning any SPS myself to keep electric cost to a minimum. By most peoples view my tank is under powered by wattage per gallon. I have 2 175 lights... but I keep my corals with in 2 areas under the lights. The way my rocks are set up it works great with good growth. My zoas mid tank have doubled heads in two months. softies grow faster than I would like. Brains and large stonies at the bottom maintiain health and color. I don't subscribe to the watts per gallon formulas.. because it's really about what type of coral and where it's placed in relation to the light.

 

2-250w with either 4-65w pc or 4-24w T5 should do you just fine. the reflector has alot to do with it, you can retro it with lumen brights or lumen arc 3. the ballast has alot to do with it also, i use hqi ballast on se mh to get more punch. then the bulb, all 10k's have different par values depending on which brand bulb and the ballast used. if you have an idea what reflector and bulb ballast combo you want let me know i have a par meter, or you can get your own par meter.

 

i think that 400's will compeltely just bleach most corals, i have 250's on my 135, hey i will trade ya 2 250's for the 400's???