tek is ho. the ho have more watts per inch of bulb.
if i were you chef, i would get retrofits. and i would get aqualux reflectors, because they dont cost as much as the iceap, nor the tek, but perform just like the icecap, which is to say, much better than the tek...
and to answer your original question chef, t5ho bulbs will last over a year at bare minimum. the day bulbs can go 18-24 months,a nd any blue spectrum will last at least a year. you can get more out of them, but its your call, most hobbyists swap them out after a year