I have a wood home built dark room sink. In order to keep equipment stationery while water flows by I have them above the floor of the sink, they sit on metal racks supported on plastic 35mm film cases. Smaller objects frequently fall through or tip over. I am starting to print up to 16x20 and even this almost 8' sink isn't long enough for all the trays. I would like to get tray ladders rather than an additional sink. These racks on the bottom of the sink are going to be an obstacle. What do other people use to stop trays and other things floating downstream in the sink?