Cleaning apparatus including a squeegee including a blade held in a spine, wherein the spine and the blade are shortenable in length. More specifically, the present invention relates to an apparatus that improves the hydrothermal growth of crystals, via the use of one or more thermally driven circulation loops. Connecting element has elastically deformable projections, which proceed from central webs, parallel to the pivot axis of cam follower such that connecting element is connected to cylindrical section in a frictionally-engaging manner.