Originally Posted by
saltn00b
well mH is metal halide, they run very hot, and use alot of electricity, but for the biggest projects, nothing penetrates the water for the wattage like the 250 and 400s.
T-5 is the bulb size (diameter ) for flourescent bulbs. they come in T-5, T-8, and T-12. with 5 and 12 most common for aquarium use. These can be NO, normal output, HO, High, VHO Very High. T-5 HO when reflected properly, can put out 300% more light than all of the other options, and can sustain pretty much anything. the bulbs last from 1-2 years, and use alot less electricity, and less heat. its a very popular and growing trend.
Have you ever used MH?
I have 2 - 175 watt MH with 130 watt PC actinics mounted in a DIY canopy. The bulbs are only 8" above the water line and I have NO heat issues. My temperature stays at 81 - 82 degrees. I don't even have any fans running.
I have NO noticeable increase in my electric bill either.
Metal Halides are not for "big projects" as you stated. It is a matter of preference. The MH will give you faster growth. The T5s will let you keep anything you want, but the growth rates will not be as good.
T5s are not as good as MH as some will try to tell you, but they are a suitable alternative.
Besides, you don't get that nice shimmer in the tank with T5s.