If you are going to put water in the tank, follow it with an acetone wash. Water is soluble in acetone and should remove any residual water with a couple of washes. You will only need a cup or 2 for each wash. Residual acetone can be easily evaporated. After washing (adding, swirling and removing) with the acetone either leave it sit for a day with the cap open or preferably blow air through it.
