Plumbing, A few new Questions

[GreenSpottedPuffer]

Thats cool that you saved the Celyons!

Anyways, back to plumbing...

How hard is it to drill glass tanks? I think I might want to just take advantage of the spare tanks I have and use them as sump/refugium. I have seen people "drill" them using a dremmel (sp.), has anyone here done this? I would be drilling relatively thin glass (1/4" I think) which actually makes me more nervous. Seems like drilling thicker glass would be easier.