I was looking at a fixture that someone reto'd from 175W to 250W. It was working nicely, and I was wondering if I could do it with a light I have. The thing would be heat. The fixture already gets hot to the touch. I know heat is a big issue with tube lights 9as far as decreasing life), but for a MH, will heat significantlly decrease bulb life and/or efficiency? Lets assume all wiring, etc was safe from melting.