Water dish in incubator!

Quick question for you all, humidity in the incubator is supposed to be what %?

i cheat i placed a wet towel right on the flexwatt that runs a long the bottom and it shoots my humidity way up there to the point i got condisation running down the glass and all.

im not sure if id wunna put something wet directly on flexwatt, seems like there might be a bit too much room for error. i keep 2 kitty litter pans full of water in the bottom of mine, the flexwatt is under them so it produces humidity and acts like a nice big heat sink thats quite even, temps stay within 1degree at all times