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Aquarium Advice Freak
Mar 28, 2011
Wa., USA
ok I know there's threads allover about lights, but I'm just getting more and more confused.

I bought a "daylight" fluorescent light bulb (6500K, 900 lumenes, 15w = 60w normal)..soooo, going by the watt per gallon rule (I know) it would take 8 of these to put my 125g at med light? Is that even close to being right? It seems kind of dim using just one on my 10g.
What kind of bulb is it? Is it a compact florescent bulb, or a T8, or what?
going off the fact that you said its a 60w equivalent, i'm guessing cfl? You really can't go off the wpg rule with any tank, especially bigger tanks. I don't even have 2wpg on my 125 and my glosso and hm are growing and carpeting quite well. This indicates it is on the higher side of the scale.
yeah those are the spiral light bulbs, trying to figure out a good way to grow plants and keep it borderline co2 needy.. I need to just break down and buy a new ballast and get both my 96w pc going instead of just the one, and new bulbs.
yeap, tweaking a hood setup for my 10 using 2 of them (spiral cfl) and I've gone and over did the light yet again (back to the green water) .. of course using the math above (I know, not a good idea) I only have 120watts of 6500K light on a 10g...meh, think I'll take one out and see if the water clears 9and stays that way) on the next water change day.

*side note I just noticed one of my grass shrimp has white/clear(ish) spots on it...any idea what this might be?
the "equivalancy" rating of 60W does not apply... it counts as 30W.

I agree with rook, lighting a large tank with CFLs would not be an efficient way to go.
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