Does that thermometer have mercury in it? I'm guessing it does. You don't wanna mess with thy stuff. I remember as a kid we use to play with it in science class.
Now... We had a call, a lady had drop a thermometer in her house, it turned into a HUGE thing. HAZ-MAT, fire dept, health department and we had to be decontaminated that stuff flys everywhere.
"When creating an aqua scape, strive for the beauty of imperfection, as its art and there is no wrong or right, it's left open for interpretation" James Findley