MH bulb/ballast combo questions

[gobbly]

I have a 250w MH hood/ballast, but the ballast isn't pushing 250w. It's stamped to run at a power factor greater than .98, but my kill-a-watt meter reads it at a power factor of .67, and it pulls around 170w. I ran it for one week and these values never fluctuated. I was told that under-powering the bulb was going to cause spectrum issues and shorten the lifespan, and I had another 250w MH I am using instead. I was wondering if it would be safe to run a 150w bulb in the 250w fixture with the 250w ballast that is only pushing 170w (around what I would expect a 150w to pull) at a PF of .67?

Also, I think this is an HQI (double ended bulb which looks like it just slides into the end's). The ballast has a cable like a computer power cord (three flat prongs), with the ballast connector being a recessed male. If I were looking for a replacement ballast for it, what 'style'/'form factor' would that be called (what should I be looking for when I shop for a replacement)? If needed I could take some pics of it...

[Bugzme]

electronic mh ballast! diy, aro's work good

[gobbly]

hey! you look familiar! :)

[carlso63]

Hey - you BOTH look familiar!!!

Sounds like you have an Odyssea MH ballast (silver colored, ridges, 3 - prong PC style cord)

I wouldn't try to outfit it to run a 150w bulb. The startup firing amperage (voltage? one of those 2) will be too high and may cause the bulb to either burn out or even burst :eek:

I have found that certain 250w DE bulbs don't work too well with these ballasts either. Pheonix 14K being one of them. Coralife brand bulbs work well; you might want to try a Coralife 20K if your current bulb looks too "yellow" on this ballast.

[gobbly]

I believe that it is an odyssea ballast. Doesn't have any name printed on it, but your description is spot on.

I only ran it for a week before I replaced it with a fixture with a better ballast, so I still have the bulb and everything (14k and looks about right for a 14k bulb). anyway, if running it with this ballast isn't going to be a problem I might end up using it for some mangroves/chaeto, or I might just replace the ballast. I guess time will tell :)