Metal Halide Questions again

[bortsamson]

I posted awhile back regarding metal halide, and I only got one response saying I would have to upgrade everthing (co2, fertz, etc etc)
Anywho
I was thinking that I probably should have asked the question differently

my tank is a 50 gallon,currently lighted by 4x15watt FLO and two 30watters
so, I wanna eliminate that mess and get two metal halide lights, and I can get them CHEAP, and I mean CHEAP CHEAP
whats the typical cost of a retail MH system....500 bucks or so?
anyways, light and ballast for me would be like 75 bucks

SO
advice please,
what should I be lookin at fer wattage
two 50s?
75s?
100s?

50 gallon long tank BTW
so one light per side

 

[bortsamson]

a week has gone by and no responses....please help!

 

[QCppg]

You need to do some research and determine the lumen per watt output of the lamps available to you, then try to match it to what you already have.

This is only an educated guess, but based on the output of sodium lamps I'd think the two 50s should be close to what you already have (120 watts mercury-flourescent). Judging by what I've been reading (http://www.lamptech.co.uk ) the efficiency of MH lighting is very similar to standard mercury flourescents. Good luck.