Little update. Lost a Rasbora yesterday and still not quite sure what happened.
Either one of two things happened. The two originals had been nipping and fighting quite a bit so something could have happened there or...
After I found it I immediately tested the water to find that adding the driftwood had dropped the ph down to 7.2! Arghhh. Its been sitting at a constant 7.8-8.0 forever. I'm quite happy that I have a better ph level now but the cost may have been mr. rasbora.
I snagged a kh drop test today just to make sure the swing wasn't from very soft water. Will post the results tomorrow.