Could I have the link to the 125 watt bulbs if it is on their website ? (aquauniverse) I searched the whole site & couldn't find them. AFAIK most PC bulbs are good for 6 months (I could be wrong) but I leave mine in for that long. reefgeek84, siding88 stated that he has a fixture not a retro, so to use T-5's he would have to rewire a fixture & possibly buy new ballasts.