I agree with 90's reefer. The Tunze is under rated but performs really well. It's set and forget. I had a 9410 DC on my Red Sea 625 and it was just slightly under size for my bio load. If the tank were 20 gallons less it would have been perfect. The tank total water volume is about 165. It's an awesome skimmer. because you just set it and forget it. I now run a Skimz and it's just okay. No real issue but it's not a wow. The tunze was far less work and honestly did just about the same.
I just switched from a large needle wheel skimmer to a Lifereef and could not be happier . It is on a 1200 gallon system and it pulls out twice as much on constant basis. Look at there sight and give Jeff a call .