I went ahead and ordered a Koralia 425 from Amazon.com. Looking forward to seeing how my tetras will react. They "fight" against the spray bar now!
Don't know enough to give you a decent answer, Ronald. But it seems like two would give you a much better distribution without the force that the 1600 puts out...
I'll post back here when I get mine and put it in the tank.
Thanks, post pics too please. People say they are about as small as an egg.
I have Cardinals in my tank now, don't want them to stress about the current too much.
The 1600 GPH one I have now is really diffused so there is not a lot of direct current which is nice.
If the Koralias are smaller, I could put them in the back two corners, this would have a much cleaner look in my tank.