Vinh -
I had the 75g planted tank for awhile. First I had two Emperor 400 hang on filters on the tank. As I know you like to have the tank very quiet, I would not recommend them although they are great filters. I then replaced them with the Eheim Pro II 2026 canister filter. It is very quiet and there is no water splashing sound. The main intake is underwater and the return is a spray bar that can be put underwater as well so you don't hear anything from that. I added the surface extracter to help suck the film/nutrients off of the surface and it made alittle noise, but not much. Excellent pump for media choices, ability to clean, and it is easy to prime (just push the top button down and it sucks in water). It did a great job at keeping the tank clean and I had a lot of fish in that tank!