Suggestions, please?

Hi! I've been lurking here looking at all your nifty projects, and I'd like some ideas.

I have this bubbler in my pond, and a couple of years ago I put a piece of clear glass under it that was laying around the house. I still like kind of the way it looks, but our water is hard, and there's always schmutz on the glass. Since I have fish, I don't want to be spraying stuff on it to clean it, and since it's out in the middle of the pond, I SURE don't want to be pulling it out all the time. Suddenly thought today that maybe this might be a good glass mosaic project. What do you all think?

If I do this, I'll need to be careful about adhesives because of the fish, water and lilies plants, so ideas in those areas would be much appreciated! And do you have suggestions as to the kind of glass that would look good and not show the gunk from the water, etc? I just LOVE the look of the tempered-glass piece that WUVIE is working on http://davesgarden.com/forums/t/693971/ but I don't think clear, even in pieces will work for this application----or would it?

Please post your $.02-worth!