bronco862;463811 wrote: i found a few sites but couldnt find what i was looking for.
how many t5 bulbs is the equivalent of one 150w MH bulb?
Your question cannot be readily answered.
It depends on the size/wattage of the T-5 and color temperature/spectrums of the lamps. Also, are you referring to 'equivalent' meaning:
PAR (photosynthetically active radiation),or
lumens/lux, which is what the human eye sees?
What size tank will you be using these on?
Below is a white paper that gives a LOT of information on the differences between MH and T5 as well as T8 flourescent lighting. This is objective information on lighting efficiency and efficacy (different concepts). The white paper does not specifically address aquarium lighting, but many of the issues addressed are relevant. In general, properly designed/applied flourescent systems are much more efficient, electrically.
This topic is still
HOTLY debated within the hobby. I probably opened a huge can 'o worms by my statements above (enter the MH police). However, there are valid reasons the hobby is moving toward lighting other than MH, such as T5 and LED's. Probably more info than you bargained for, but my advice is to educate yourself, THEN make an informed decision. It sounds like you are well on your way. Good luck!