Hey thanks. I've actually had a C3 on my 29 gallon for about a month now. It works great. The thing is, I just put a C2 on my 10 gallon a couple days ago. It seems to work great too, but I noticed a difference between the two, and I didn't know if it was a problem or not. So, you know where the water comes out on the left and flows over the top of the trickle chamber? Well, on the C3, water's flowing out of there at a pretty good rate. But, on the C2, there's little or no water flowing on top of the trickle chamber. The filter's still filtering. There's plenty of water going through the system. There's just no water on top of the trickle chamber. Any ideas?