Wow, mine lasted for a long time, but eventually it got a leak and blew...
I ended up taking it apart and resealing it w/ silicone. Seems good now, but I just started using it again.
The other thing is I replaced the bulb with a 5watt instead of the 10watt it came with. Should be plenty of light considering the chaeto is growing basically against it. with the 10 watt bulb i did notice that the chaeto right against the light (touching) was white..