What can be done to decrease suctioning from a tracheotomy at night? and what's the best sleeping aid for staying asleep at night?

Metal Trach : In my experience metal tracheostomy cannulas tend to irritate less the respiratory tract.

Fluid adjust?: Change fluids and timing to see if that is an issue. Congestive heart failure may precipitate nocturnal lying down pulmonary fluid. If the suctionable material is purulent-pus then antibiotics may help. Would not use sleep help beyond Benadryl (diphenhydramine) in this person.