I've got lily pipes on my 306 and it flows out slow like that as well. I figure it was just the design of the pipe that made it appear like that. I also had switch back to the stock inlet because the filter was noticeably noisier with the lily pipe one.
Sorry to hear that. To Fluval's credit my filter has been dead silent regardless of what intake or exhaust I've used. I used the lily glass intake in the past but I accidentally tally broke it when I was rearranging the tank a while back.
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