Jonny Fly
420 Member
I'm not sure when it's time to replace my HPS bulb. I traded a guy a bunch of grow light equipment for some cuttings. Some of the bulbs were obviously used and some appear to be new or at least used slightly. It's easy to tell when to replace a MH bulb, the ark chamber gets blackened. In the picture, the three 1000 watt Eye Hortilux bulbs look new, at least to me. I used one if them for one blooming cycle. I didn't keep track of which one I used, and you can't tell by looking at them which one it was. I burned it in a cool tube. The 400 watt Eye Hortilux, to the right of the 1000's is used and it looks used to me. The base of the bulb has turned that silver/black color. The 600 watt bulb on the far right came with a 600 watt digital ballast I purchased. I only used it for a few weeks, but it's obviously used. The base has turned dark and the bulb itself is turning orange. I burned it in a gull wing reflector. I'm wondering if temperature has something to do with it. Maybe the 1000 watt bulbs look new because they were used in air cooled reflectors? I've heard one should replace MH bulbs every six months and HPS bulbs every year. I've also heard to look for black specs inside of the element. The 400 and 600 watt bulbs have black specs and only one of the 1000 watt bulbs has some, but very few. I'd really like to use the Eye Hortilux bulbs a few more times. They're about $100 each. So, if anyone out there can give me some information regarding when an HPS bulb should be replaced I'd be most grateful, thanks, Jonny Fly...