My LFS was able to get a hold of these All-Glass mini compact lights
so I bought one yesterday. $12.99 (versus $6.99 for a 4000K lamp at
Lowes).

It screwed into the mini-box2.5 with ease. Its a tall-skinny light.
Not a short-fat one like the HW store sells. So I didn't have to
remove the splash guard.

After plugging it into the mini-bow 2.5, it is much brighter than the
incandescent. The light appears 6400K. It's very white.

Only problem I see is with the tank design itsself. The left side of
the tank is lit much more than the right side. I better get the
left-side Betta some sun-glasses.

Maybe I'll try reflecting the light to the right-side with some shiny
metal.