2004 OttLite
13w 4000k PL flourescent

I picked up this up used the other day for reasonably cheap, however it seems to have an proprietary bulb consisting of a 13w tube using a 9w connector.

I have little knowledge of the electrical side of these lamps so I thought I'd ask if I just used a 9w bulb in it like the connector it takes would 13w be a hazard or destroy a 9w bulb?

The bulb is working fine but it's been used a lot and I expect it could be brighter with a new bulb which cost more than I paid for it and a regular 9w would cost about a 1/5th of that.

Here's some pics and thanks for any advice.

Does this light turn on instantly without blinking?  You may be able to get away with a 9W G23 lamp, but assuming this is instant-start electronic, you might run into problems unless you're able to disassemble the new lamp and remove the starter.  How does the length of the supposedly 13W tube compare with a standard 9W?  It might overdrive the 9W if they're the same, producing similar output to a new Ott tube.  If the 9W is shorter, it may also produce less light.  The lower-wattage lamp could also be potentially harder on the ballast, and cause it to run hotter.

Does this light turn on instantly without blinking?  You may be able to get away with a 9W G23 lamp, but assuming this is instant-start electronic, you might run into problems unless you're able to disassemble the new lamp and remove the starter.  How does the length of the supposedly 13W tube compare with a standard 9W?  It might overdrive the 9W if they're the same, producing similar output to a new Ott tube.  If the 9W is shorter, it may also produce less light.  The lower-wattage lamp could also be potentially harder on the ballast, and cause it to run hotter.

Thanks for the reply.

I'm not sure if I would call it blinking but occasionally I'll see a quick flicker as I turn it on, most of the time not.

I'm not sure about the lengths at the moment but I have an order of 2 desk lamps that use 9w PL bulbs on the way so I'll be able to look when they arrive.

Yes good point about the ballast potentially running hotter, don't really want to destroy that either.

There is another option of swapping the lamp to a 13w lamp holders (GX23 I think they are) which I might do if a 9w bulb in a 13w fixture is a bad idea. 

I presume that has an electronic ballast, though the Ott-Lite website says they switched in 2008.  I have an Ott-Lite from 2001 which has a standard 13W GX23.  As I previously noted, the most pressing issue if it's electronic could be the need to remove the integrated starter.  I'm not sure why they didn't switch to a 2GX7 socket which would have allowed for the 4-pin lamps normally used with electronic ballasts.  If such a socket would fit, that might be the best bet to accommodate a standard lamp.