When the tube is filled with many dry shuttlecocks at one time, they will soak all the moisture.
Therefore, it may be a challenge to raise the humidity to the optimal 70-80% at the start.
This tiny challenge is dealt with by placing the foam roundel the end of the tube where the shuttlecocks are taken from in the first weeks’ time. Alternatively, you can just fill up 6-7 shuttlecocks in the tube at the start.
Should the process progress very fast, you can just increase the humidity of the shuttlecock with a little spray of water before placing it in the tube. The water-sprayer should be set to the finest atomization and kept so the water-cloud fall down over the feathers. For this little task you can place the shuttlecocks in an egg tray.
Always remember to fill the tube with shuttlecocks when you come from badminton, so they have plenty of time to absorb the moisture. At the same time, you can just check if the foam needs a little more water. But avoid putting so much water on the foam that the water run down the tube. The optimum would be if the shuttlecocks had been in the tube for at least 14 days before coming into play.