Broken thermometer!

[DavidH]

I use those glass thermometers in my holding tanks.
One broke the other day and I didn't realize it till after w/c. Any one know what's in these things, I hope not mercury.

Any info appreciated.
Dave

I have had several broken.... on many occasions... I don't believe it is mercury, they use some other liquid, which I assume it not lethal for the fish.... OrElse I would have lost quite a few by now...