when are MH bad?

How does one know to change their MH bulbs? aside from the time they spent connected to the tank. Is there any tell tell signs we could look for. I am talking about Single ended Mogul socket bulbs. They are a bit expensive and wanted to know aside from the 18 month life span is their anything we could really look for?

 

on average at 10 hrs per day a life span of about 10 to 12 months is max or 4,000 hrs depending on who made the bulbs also not all are as long lived as others. also electricial power to branch circuit and peaks and levels of wattage and amps from pole then the transformers used make very small a difference.I run mine at 6 hrs aday for like 16 to 18 months and its about time to swap them out in april.

 

About the only way you can tell, is to use a par meter and a spectrum meter to see how much the intensity drops and the spectrum changes.

With that said, I normally give suggestions based on the color temp, 6500k 16 months to 24 months, 10,000k 12 to 16 months, 15000k 9 to 12 months, 20000k 6 to 9 months. But that is just a suggestion, and different bulb/ballast combo's will ware out at different rates.

Kim

 

well when there really bad they don't start, but i think you want to catch it before that