X-aqua X-Inout device instantly struck us as one of the most innovative and potentially very popular marine aquarium products of InterZoo 2010. The X-inout looks inocuous enough but something about the fluid dynamics of the return part of the device causes the pressurized return to pulse without the use of any moving parts or a diaphragm. We’ve looked all inside of this thing with small mirrors and LED flashlights but we can’t see any mechanism or construction to suggest how the X-inout works. Nevertheless, the X-inout works and it works well producing a pulsing of the return line which can produce attractive large ripples when driven at certain flow speeds. The X-inout has already been adopted by an American distributor and we hope that these will become available for a reasonable price stateside within 30-60 days.