I just asked the factory for an update and was told 3 more weeks and we should have them. I think for a skimmer I prefer AC as it is cheaper and the pump lasts longer. Not sure I want to deal with power supplies and controllers when it is not doing anything for flow. I agree on the 9004 surface skimmer, but the newest 9001 has a bubble trap sponge included, while not perfect, it will help, also the surface skimmer can be improved by adding the floating surface skimmer from an Eheim Surface Extractor.