Guys I think what most of you are missing is what each of us has to pay for electricity. If you have to pay 34 cents a KWH you can not afford MH. But in my case I looked at LED on my 300 but at 6 LED lights it did not come out to replace my 3 x 250w MH in the short or long run at 10 cents a KWH. If I had to pay 34 cents I definitely would not have a 300 much less MH lighting.
Actually, I am not missing that point at all. Thats what I am paying as well; $0.10/kWH.
Let's look at an honest example for people who may search this in the future, but let me preface by saying this:
I am not pro-LED or pro-MH. I set-up my tank w/ a DIY LED fixture, but I have all the components I am going to list in storage in case I want to switch to metal halide. When I set-up my tank, alot of people were on the fence about whether LED will grow corals as well as MH, so I bought barely used MH equipment since so many people were switching to MH. I have it if I ever feel the need. This tank has been growing SPS for almost a year, so I honestly dont feel I'll ever need to switch. Also, utility bills mean nothing to me. If MH grew corals better, but cost an additional $100 in utilities, so be it. I spend 3-4x that per month on aquarium related stuff. so...
I have a 220 6'x2'x30" high tank. Option #1 is 3x 250w radium supplementing w/ 4x80W T5s. Option #2 is 120 LEDs, dimmed by an Apex. With a par meter on hand, myself and 3 other experienced SPS growers set-up my LEDs to match the outout of 250W MH. That number is 68% using 3W Crees w/ 60* (maybe 70*, cant remember) mounted 14" off the water line.
I run 12 hour RBs w/ a 2.5 hr ramp up and 2.5 hr ramp down. 9 hour whites w/ the same 2.5 ramp up/down.
For the example, lets run 10 hrs of actinics w/ 6 hours of MH.
LED 60 blues, 60 whites: blues during 2.5 hr ramp up = 39% 70.2W
blues at 68% for 7 hrs = 122.4W
ramp down = 70.2W
whites ramp up = 70.2W
whites @ 4 hrs at 68% = 122.4W
ramp down = 70.2W
$6.15 per month is what my LED usage costs me with ramping up/down @ $0.10/kWH used.
MH
3x 250W= 750Wx 6 hrs/day = $13.50 per month
4x80W T5s x 10 hrs per day = 9.60
$23.10 w/ MH/T5 actinics /month
$16.95/month savings in this scenario MH/actinic vs. Leds
To try and be as accurate as possible, lets factor in the MH heat scenario. Lets assume I have to run 300W of heater to make up for heat no gained from MH lighting. As a guess, said 300W heater has to run 30% of the 6 hr photoperiod where the MH would have supplied the water with heat.
That equals $1.62 per month.
This brings the savings down to
$15.33 or $184 per year
LEDs are advertised at running (properly cooled) 50,000 hrs before spectrum starts to shift. Thats 11.5 years at 12 hrs per day.
2nd year we have to buy 3 250@ radiums @$80 = $240
4x80W T5s at $24.00=$96.00
Total bulb replacement $336/year
Money "wasted" with MH/actinic at 1st bulb replacement $520
3rd bulb replacement $1560
6th (year 7) $3120
9th (year 10) $4680
10th (start of 11th year, LEDs assumingly starting to shift) $5200
Notes to consider:
-Will LEDs last 11.5 years?
-Heat from MH in the summer will make your AC run longer, and AC pulls BIG wattage.
-Your house temperature where the tank is/what temp your tank runs at will have some impact on cost.
-Does LED grow coral as well as MH?
-All these statistics are based on 10 cent per kWH. California and some other state have prices in the 30-40 cent per kWH. Take my figures and multiply them by 3 or 4 and see the difference.
-On start-up, I built my LED set-up cheaper than I could have bought new MH equipment. Selection of LED choices will affect long term potential savings.
There you go, folks. I've tried to be as fair as possible. If Ive made an error, please correct me; I am human and mess up occasionally:worried: As for MH equipment picked, thats what I
would have used myself.
Happy reefing!