^^^ Sup Flatlander.
I actually had a pretty knowledgable LFS owner tell me a couple of months ago...MH bulbs dont need replacement until they burn out????
He said hes checked par rating as the bulb ages...yes the par output decreases...but not enough to be a factor to change the bulb.
I have nothing to back this... Just FYI
that is true, sort of, the reason they lose par value is the electrodes inside the lamp splatter a bit on start-up in the start-up. small amounts of the electrode coat the inside of the envelope and sort of tint the glass. this is one of the main advantages of a good e-ballast, they fire in as few as 2-3 cycles, as apposed to magnetic which take around 40 cycles to fire
halides do create more UV which encourages the corals to produce more pigments which are the colors we like to see
the one point, and it is actually 2 fold, that I would take issue with is a matter of efficiency, which translates to heat and electric bill.
in short, halides will give you more light for less money. that is to say they are more efficient. they produce less total BTU per lumen and require less watts per lumen. what this means is that if you ant to achieve the SAME PAR VALUE with T-5, the T-5 setup will require more watts and produce more heat than a metal halide setup producing the SAME par value. this is not true with 20k halide lamps
I probably missed it but what K is best for SPS coral growth? I currently running 150Watt 14,000K Phoenix bulb. I have a bunch of SPS now and growth is pretty SLOW.
6500 +VHO actenics
Edited by filefish949, 07 December 2007 - 12:53 AM.