Neighbor moved overseas and gave me their dwarf frog in 2 gallon tank. Was fine first couple weeks now there white cotton growing from mouth/feet. Think its a fungus. Not sure what to do. Need an expert to take a look at picture and let me know what medicine I can get for him. He doesn't look like hes going to make it through the nightI changed 20% bottled water daily since this started and there is a filter in tank. Please help. Thanks for reading.