I've got a C13 with a 250w MH. The inline fan and carbon filter work great but the heavy duty Intermatic Digital Timer that the MH is plugged into seems to have a mind of it's own. There is rarely a correlation between when the light comes on and the settings on the timer. And yes, I can program it to work on smaller CFs so correct programing is not the problem. Please, can someone recommend a good timer? Digital would be preferrable but whatever is consistantly reliable and SAFE.