its small and does a good job of getting flow in the rear corner opposite my return. yeah, its not going to knock your fish around the tank or make your sps go nuts, but it is good for just adding a bit of flow IMO. plus the friking thing is tiny, and the #1 is huge...
Just for the record, I'm using this one for flow along the back of the tank. Things have gotten so large that they're not letting the flow move as it used to Hopefully the 1 does the trick Need to get some flow on my froggies/hammers and so more light cause my damn anemone is half of the tank now