It's a good filter, I only put the ac110 ahead of it. I used to used them on my tanks just getting rid of my last one some months ago. Now using all AC's.
It is louder then then the 110's. That's my only knock on them. I liked mine they worked well for me. So if your on a budget get the 400. If not get the 110 is what it comes down too. For me anyways.