Carbon paddle shafts are hollow, and water gets in through a crack or a worn tape at the joint. It sloshes around, adds weight to your stroke, and salty water also prevents any epoxy repair from curing properly. But how to get it out?

Drilling a hole is not enough, the water stays "glued" inside by surface tension, unless you make a hole big enough, that will then compromise the paddle strength.

The trick I use is to drill 2 small holes (~3 mm), one on each side, about 20 cm under the handle. Now, face down, the top hole into your mouth and gently rock the paddle so the water runs toward the bottom hole, then blow in the top hole hole like a flute — the water comes out of the other. Works quite well, no need for bigger holes.

To get every last drop out, let the water flow over one hole back and forth while blowing through the other at the same time.

Dry the shaft before repairing it: epoxy does not like salty water for curing. A hair dryer blowing into the holes does the job. A little residual water is not a problem.

Seal the holes afterwards with a dab of epoxy resin or glue with some microspheres of glass fibers, or UV repair kits like Solarez or DuraRezn, or epoxy paste, or a self-amalgamating tape. Just be sure to tape over it while curing so internal air pressure changes with temperature variations will not blow the repair away.

Note: I first posted this trick on the Gong Galaxy forum, in 2014.