Dear Cyberbuds, Does anyone have a rate of evaporation chart or figures of what is normal evaporation . We have a small pond "puddle" only 3ft sq surface area . The water is refilled after evaporation occurs as necessary.This is the first time we have created an exhibit with water in it. We are loosing 1/4 -1/2 every three days. RH in our gallery is 55% and there is moderate air movement over a rock structure above the pond. Anyone have a similar exhibit and how did you slow down the evaporation or did you resort to a float and valve assembly to fil up the loss . Would appreciate ideas . Len Hambleton - Objects Conservator North Carolina Museum of History 5 East Edenton Street Raleigh NC. 27601-1011 [log in to unmask] 919-715-0200 x244 "Information in the spirit of sharing,catch the wave!" Opinions expressed in this message may not represent the policy of my agency