The only issue I had was when I spilled about 3/4 of a gallon. I thought I got most of it up, but some went under the baseboard. Now, when I did the floors, I thought it was a good idea to line the subfloor with killz, yea that didnt help me. The only places I couldn't get the killz to was between the walls, and the water found its way into the wall, and was dripping from a door frame in the room below.
My wife was not home, and shall never know of this.
My next tank, cause we're all planning one, will have some pond shield type liner in the stand, and some type of matting under the stand, so those spills dont seep into the wood.
As for day to day stuff, I try to have towel or two down when doing water changes, or anything similar.