Supplemental Feeding Force-feeding Liquid diet First, attach a silicone tube, which is sold by the cut at home improvement stores, etc. It's gentle on the gums, so you can feed with peace of mind. (I used a 4mm diameter tube cut to a few centimeters, but if it's too loose, it might come out during feeding, so be careful not to let them swallow it.) Will be shipped via postal mail.