MH bulb won't work

[hagfish]

I've got a MH fixture that I bought used about a year ago. It needs a new bulb pretty bad, and I have some for another fixture that I thought would work, but they don't. It's a single ended 250 watt fixture. Here's some pics of the ballast and bulb. I circled a piece that's different on the bulb than the other bulbs I have. Maybe that will help you to tell what kind of bulb I need to buy. That's my question, what kind of bulb to put in this.

http://i46.photobucket.com/albums/f148/hagfish/lights/ballast.jpg

http://i46.photobucket.com/albums/f148/hagfish/lights/ballast2.jpg

http://i46.photobucket.com/albums/f148/hagfish/lights/bulb.jpg

[rams]

Any kind of info on the bulb and some more on the ballast? I have never seen one but is the part circled an internal igniter a European bulb? If the ballast has an igniter that might spell trouble if used together.

Wish I was more help. Never really read into MH setups.

[TWINPEAKS]

I was told the with the magnetic type ballasts you have to have a probe start bulb.Will the bulb work in any other fixture?

[hagfish]

Ramtheory, I posted more on the seasl forum. But basically I found out that the bulb is a iwasaki 6500k and the ballast is actually mercury vapor. From what I've found so far, that bulb is the only one available that is suitable for aquariums. It actually doesn't look that yellow though, even after being a year old. I'm trying to decide if I want to buy another bulb like it or rewire to a different ballast (I have another already).