hey i have a 200L tank which I am setting up for a reef tank. it already has 3x t8 lights (2 white one blue), can I simply put t5 bulbs in or do I need to wire in new fittings for them? the bulbs already in them are 90cm, 30Watt bulbs, 10000K from sylvania... cheers.

T5 are higher wattage

so do I need new fittings? I might buy that mh of you jetskisteve... the one on trademe

The tubes are thinner so yes u need new endcaps etc

Anyone know what voltage T5s run at?

I know they're generally higher wattage, but once you have the endcaps if the voltage is the same, you shold be able to use say a 50 watt 5 foot T8 setup to run a 3 foot(or whatever) T5?

3ft=39w

4ft=54w

5ft=80w??

T5 and T8 endcaps aren't compatible with each other. T5s's are thinner than T8's.