I have seen some discussion on bottle brushes for cleaning these tube type bottles. I may suggest an alternative that will benefit both you and the fuzz butt... Most grain and feed stores, Wal Marts, Pet Stores, all kinds of places... sell large water dispensing units for less than $10. For $5.99, I got one that holds about 2 gallons. It is only two parts, a plastic see thru jug and the base. The base simply twist locks on. WHen you turn it upside right so the water comes out, air pressure holds the rest of the water in and will dispense as the level lowers. The water comes out into a trough about 1.5 inches by 4 inches wide and long and about an inch deep. This lets the fert drink most naturally and there is never a drip or noise when they drink. Is good for about a week. To clean, just remove, and wash as you do other things. THe mouth of the bottle is wide enough to put your leg in. Ha! Mine is hung on the outside of the cage and held in place by small bunji cords so the ferts don't push the thing out. I made a wood platform for it to rest on, but had to cut a small hole in the cage to fit it in. Now, I can get at it from the outside and service it once a week in only minutes. I did the same with the feeder. Makes life much easier for us each. Gordon, Byte-me and Nibble-ed [Posted in FML issue 2966]