Originally Posted by sailingdog
[B]pre-filling the bowl by pouring a little water into the bowl is probably a good idea before using it for solid waste...since it will allow the head to flush more cleanly...
Yup, I've been on a few boats that would not fill the bowl with the switch in 'flush or fill' mode. Used the hand held shower head to wet the bowl, switch to 'dry' afterwards and pump. Use additional water from the shower head as needed to completely clear the bowl. Although quite capable, I've never clogged one yet!