I ended up buying a Marineland 300W Visi-Therm Deluxe from the LFS. I couldn't find the 250W heater. One quick question though. Is the on/off light supposed to be on all of the time? Mine seems to go on for long stretches of time and turns off for stretches of time. My tank isn't up to 79 just yet. I just want to make sure it's not defective before I can't return it.