How big is the skimmer base? if it's 8"x4" or so, you could take a 4x4" piece of wood (make sure it's untreated), cut two pieces that are 6.75" tall and bind them together with wood glue. Then, on the top surface, glue on some type of foam or insulation. If you want, you can even glue on some insulation on the bottom of the aparatus too.
If you want, you can even paint the piece of wood the same color as your stand.