I was looking into this and talked to the main distributor from the manufacture in Poland.
There are many factors on to choose the 120W or the 160W units. It really boiled down to how deep your tank is. If you have a standard 24" or shallower tank you can go with the 120W. With the deeper tanks is when you need to start looking at the 160W unit.
Now lets talk price.
A great set of LED's is going to run you about $1,000 to $1,200 for the master unit and $900 to $1,100 for the slave units. The true savings is over time not upfront. With running your LEDs full blast (which I doubt you will) for 8 hours a day you will get about 15 to 16 years out of them 12 hours a day 11 to 12 years.
Now add it all up
Lets say you need 2 MH units. a great reflector $150.00 each (300). Ballast $150.00 each (300) for a good one plus tax or shipping etc. Bulbs $90.00 each ($180.00)
So to start you got about $750 to $800 into your MH. Every 9 to 12 months you are changing the bulbs. ($180) If you change them at 9 months that is 16 times in 12 years. 180 x 16 = $2880.00 and 20 times in 16 years 180 X 20 = $3600.00 now add your original $800 for the set ups.
$3,680.00 for 12 years MH
$4,400.00 for 16 years MH
This does not include the electric to run the equipment nor does it include your actinic lighting
Icecap 660 ballast with wiring is about $160.00 new
Bulbs are around $35.00 each (3 to 4 depending how long you they are)
changed every 9 months also
$35.00 times 3 bulbs = $105.00
$105.00 X 16 (12 years) = $1680.00
$105.00 X 20 (16 years) = $2,100.00
Of course some might use cheaper bulbs, buy used, spend more or less on the ballast etc. This is meant to be on the average
So to run the MH lighting with actinic sup is will cost you (Electric not included)
$5360.00 for 12 years
$6500.00 for 16 years.
For LED to run for same amount of time just adjust the K value you are looking at for one master and one slave unit.
$2,000 to $2,500.00
Now look at the PAR ratings that have been posted in these forums:
when you talk about PAR it is good to have some point of refernce. here is the link melvesreef PAR data on different MHs:
http://melevsreef.com/pics/08/05/par_wflow_new_bulb.jpg
google for T5 PAR #s and you will find similar pics.
as far as 120W unit,
16,000k light temp:
2" depth - 1581 PAR
12" depth - 551 PAR
24" depth - 249 PAR
As for myself I believe I will be switching over to LED's shortly, just waiting on the report from Sanjay.
I almost forgot, The heat from the MH compared to the LEDS. MH should be off the water 8 to 14 inches and you still have to use fans or chillers in some cases. LED's can be placed right on top of your tank and used as a lid, I have not seen or heard anyone using a chiller with the LED's. That should give you a good idea on the difference in the heat.
HTH
