So I just took the cover off of my filter and I found that half of the inflow of tank water was going over the wall of the filter and skipping the filter media part and going straight into the biological part of the filter. Hopefully this makes sense. I didnt know how else to explain it. What kind of problems has this caused? Would it be an answer to the nitrite spike I just had? I kinda fixed it by lifting up the filter media insert a little and now it doesn't overflow and bypass going through the carbon filter. I am looking at buying a AC70 for my 29 gallon cuz I'm not really happy with my aqueon filter.