Man, I just bought one tonite at Eco Reef! Put in on my Maxi Jet and it blew like mad! I only have the baby 400 too...but with my little 20g it's actually too much, but for bigger tanks would be awesome! I wanted to upgrade mine because it just got clogged up all the time with the small holes in the screen...and it's definitely an upgrade! Thinking of putting it in the hubby's 39g when he sets it up. Also it seems to have flow like the Koralia too...but alot more intense than the one I have (the smallest also).