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Metal Halide users, how long is your MH photoperiod?

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Having seen a few topics pop up at the SPS forum over at RC about color and photoperiod, I'm curious what other locals do. Not so much to change my view on a topic, but I like to know what others do. :D

I've gone from a long photoperiod 9 hours a day, to a relatively short one 5.5hours, and have seen a significant improvement in coral colors. Granted there are a handful of other reasons this could have occurred, so I'm in no way saying the light was the sole reason of it, however I haven't seen any BAD things occur due to the reduced photoperiod, so while PG&E might not be happy about my choice, I am.

Also I was stuck before with single ended bulbs, over an 18" wide tank with lumenarc type reflectors, so there was no other space for other lighting, however moving to a 36" wide tank, not only did I ditch the reflectors, I went DE, and T5s.
 
G

GreshamH

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For years I ran only 5 hours but then a timer crapped out and they all got stuck onto one timer for a long time and closer to 7 1/2 hours. Things paled out at that length so recently I've gone back to more timers and 6 hours. Things are getting a bit darker now :D
 
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I lowered my MH photoperiod to 6 1/2 hrs and will probably go down to around 6. I used to have them on for 8hrs.

What kind of DE MH and T5 do you have Mike? I am considering changing to different bulbs and was wondering what combination of DE MH and T5 looks good.
 
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Aldie, I use 14k Phoenix bulbs (250w) and a combo of ATi Blue plus and UVL Super Actinic T5s, I highly recommend the blue plus if you have a choice between one or the other, they put out impressive light numbers for a blue bulb.
 
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I run my 150W 14K Phoenix DE bulb over my 20 gallon tank for 7 hours. I have my T5 actinics on 2 hours before and 2 hours after.
 
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I have mine on for 9 hours, but have been thinking of reducing that for some time now (just keep forgetting to do it).
 
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In both my Frag Tank and Display Tank I have them running a 6 hour MH photoperiod. With the move to 400W's in my Display tank I believe I will be moving down to a 5 hour photoperiod. I also run a pretty lengthy T5 actinic period running 2 T5's... a D-D Giesmann Pure Actinic bulb and Actinic+ bulb over each tank for about 12 hours.
 
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I follow the suns photo period, every 3 weeks or so I increase it 5-10 minutes, in the fall I decrease as it goes.
 
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lights on at 3:30 and off at 1:30am
 
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I run my mh for 7 hours and t5's for 9 hours but I also am considering cutting back an hour on each and see how it goes.
 

Ibn

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Iwasaki 50kk for 7 hours; Giesemann actinic plus for 11 hours.
 
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MH on for 6.5 - 7 hrs. Actinic is kinda long at 12 hrs. but allows for more tank viewing. Thinking about cutting MH down to 6 hrs to save on PG & E.
 
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[quote author=badbread link=topic=6581.msg84789#msg84789 date=1235676611]
I follow the suns photo period, every 3 weeks or so I increase it 5-10 minutes, in the fall I decrease as it goes.
[/quote]

Do you account for clouds as well? haha.

I run mine for about 6 hours on my frag tank. Staggering them by half an hour. Actinics are on for about 8.5 hours.
 

Ibn

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Loving it so far, Gresh. That Iwasaki bulb is bright as hell though and seems to burn a crisper color with the Giesemann ballast than with the Aquamedic. I can't really tell the actinics are on; I've looked through the side of the fixture to make sure that they're on on more than one occasion. :P

I'll be trying out the UVL super actinics and the ATI blue plus as well to see if either of them produces a bluer look when stacked with the MH.
 
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