Koralia 1 or 2 for a 27 Gallon

[SmallFry]

Hi,

I'm looking at getting some more flow in my tank as stuff keeps settling out on the sandbed, but I don't want to create a sandstorm. I did have a 350GPH powerhead that was stirring up some sand, but that was a much narrower stream - it's now running my skimmer. I was originally thinking of the koralia 1, but I heard that the flow was a lot broader and more gentle so I was thinking maybe a 2 would be the way to go.
I'm fish only with live rock at the moment, but this may change in the future. Any thoughts/opinions would be appreciated..

Rob.