Old bulbs = Algae problems?

[Delphinus]

Christy, where did you get your ballasts from and can you tell me a brand/model # at all? PM me if you prefer. Thanks..

Bongy, maybe I need my eyes checked too, but I too can only barely perceive a difference between the two sides and I'm not sure if I'm imagining it because the suggestion is there that the right hand is maybe slighlly bluer. Perception and psychology is a funny business. What's throwing me off is that right in the center at the top there is a bit of a spot above the congruence of the light rays that is a bit darker. This gives me the impression that there is a line dividing the two sides. So the two sides different enough that I can maybe perceive that there is some kind of difference, not they're not different enough that I can quantifiably identify what that difference is. I guess maybe Jack's right, the right hand side is slightly bluer. I think.

Jack, I spent at least 2 minutes searching the web for info when I was wondering about this. And it occured to me that most 250W ballasts we're using must be the MH/MV versions. I know that they're "fine enough" because that's what I run, and I'm not unhappy with the results. It's just that ... I never really noticed a huge difference between the R and the non-R, and I'm wondering if maybe I WOULD notice more of a difference if I had only the H37 ballasts. If I could find a H37 that wasn't also a M58 then I'd just buy it to try it and settle the question in my mind once and for all. Oh well...