As the relatively cooler weather in Eilat during winter results in less call-outs I've manged to test a few new ideas.
Process timers are normally scrapped when 1 of the functions fails.As is often the case the thermostat switch is often the first to go.This still leaves all the defrost and fan control functions usable.Maybe not by any reputable refrigeration company, but for a garden sprinkler system or vacuum pump timer for inverted aquariums it is ideal.
I drilled a series of 2mm holes on the water line.When the vacuum is applied the water level rises in the inverted section and the lower tank water level reduces until it exposes the air holes.At this point fresh air is drawn into the upper aquarium.
I suppose for refrigeration engineers the idea is staight forward.But for a number of aquarium keepers it has been slagged as "over-complicating" an already complex hobby.Not so much in the United States and Canada where a number of ennovative concepts evolve.
Bottom line is, these inverted aquariums and tunnels provide a far greater freedom of movement which greatly enhances their dwelling conditions.

http://www.youtube.com/watch?v=A1qjNpBxt6E