I have been running a number of MAGs external for a year: 3 of them have died. They over heat and distort the hole the impellor turns in. I have never had a problem with them running internally. And the MAG Co has always replaced them without a question, but it is troublesome to go without one...
I have seen significant variations in the length of time a VHO and a PC bulb can effectively last. Does anyone have a good idea? I am setting up a new aquarium and have not decided between the two types of bulbs. Currently I think the VHOs provide better color, are 1/2 the price, and can grow...
