I have a 75 gallon sw tank connected with an external wet/dry filtration system. The aquarium is in my bedroom. The return pump is very noisy (even if is a Quiet One 4000...) and this make me unable to sleep at night. So the question is: can I shut down the pump off at night ? is there any problem with drying bio balls ? in the morning they still look a sort of wet, but I am worried that the inactivity of the filter for ~10 hours a day may create problems with the nitryfing bugs on the balls. Any idea ?