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Traill
05/18/2008, 09:42 PM
can someone give me some help with lighting lingo? If i have two 150 MH bulbs, does that mean i have 300 watts of MH? I see people recommending 250 and 400 watts, but i don't understand if this is total wattage or the wattage of each individual bulb. thank you!!

Aquarist007
05/18/2008, 09:48 PM
<a href=showthread.php?s=&postid=12567380#post12567380 target=_blank>Originally posted</a> by Traill
can someone give me some help with lighting lingo? If i have two 150 MH bulbs, does that mean i have 300 watts of MH? I see people recommending 250 and 400 watts, but i don't understand if this is total wattage or the wattage of each individual bulb. thank you!!

yes, the usually quote the wattage per bulb

HaKs310
05/18/2008, 09:48 PM
That would be the wattage of each Individual bulb/fixture, not total wattage.

alpha0r
05/18/2008, 09:48 PM
MH lights come in 70, 150, 250, 400, and 1000 watts. Total wattage would be all your lights added togeater 150+150= 300. People recommend 250w MH for tanks deeper than 24 inches.

Aquarist007
05/18/2008, 09:51 PM
<a href=showthread.php?s=&postid=12567411#post12567411 target=_blank>Originally posted</a> by alpha0r
MH lights come in 70, 150, 250, 400, and 1000 watts. Total wattage would be all your lights added togeater 150+150= 300. People recommend 250w MH for tanks deeper than 24 inches.

I agree---another way of looking at the wattage is how far the light penetrates
eg a 300watt halide will penetrate to twice the depth of a 150 bulb
You do not however combine the total wattage for deeper penetration

Traill
05/18/2008, 10:39 PM
thx i think i get it. so it doesn't matter if i had twenty 150's, it's still only 150.

Aquarist007
05/18/2008, 10:43 PM
<a href=showthread.php?s=&postid=12567711#post12567711 target=_blank>Originally posted</a> by Traill
thx i think i get it. so it doesn't matter if i had twenty 150's, it's still only 150.

not quite, you would be supplying twenty times the light energy or lumens but they would only penetrate as far as the wattage of one of them.

eg if a 150 watt halide penetrates to a depth of 18 inches then in your example you would be applying 20 times 150 watts of light energy to the max depth of 18 inches