I think that almost any ballast can be used on a tank's lighting system. I mount ballasts on the back of the light strip, rather than inside like the original would be. That means that even a ballast that is not designed for high humidity locations will continue to work fine for years. The light strip itself requires the bulbs be located inside the light strip but does not care a bit about the ballast location. The ballasts mounted outside the light strip also tend to run cooler than one inside with typical ventilation. That means they will last longer, without replacement, than the original equipment ballast would have.