So how is that "wicking system" possibly effective enough to wick moisture at anywhere near the rate that it accumulates in a euphonium? I'm really skeptical about that. Also sounds messy -- especially if you have more than one. Another goofy idea.
If you need to glue your water key "cork" (or, if you wish, "gasket") back in, just about any kind of stick-em will work. A lot of people use contact cement since it's easy and relatively inoffensive.
Gary Merrill
Wessex EEb Bass tuba (DW 3XL or 2XL)
Mack Brass Compensating Euph (DE N106, Euph J, J9 euph)
Amati Oval Euph (DE 104, Euph J, J6 euph)
1924 Buescher 3-valve Eb tuba (with std US receiver), Kelly 25
Schiller American Heritage 7B clone bass trombone (DE LB K/K10/112/14 Lexan, Brass Ark MV50R)
1947 Olds "Standard" trombone (Olds #3)