I recently acquired two of these ADF's about a week ago winning them from an arcade. i just got back from a fishing trip and brought home some of the river water and seaweed for them. since then, i've cleaned the tank and filled it with the river water and redecorating the tank a bit. i've also noticed that since i've done this they have been making these buzzing sounds. what are they? are they good or are they bad? im assuming they are good, but you guys seems to know more about them then i do. thanks and i hope to learn more about these frogs for they are AWESOME!!!