Question: How do you clean an aquarium filter?

  Options: 
 A. It is important to protect the beneficial bacteria in the aquarium's filter, because this is what will process the toxins from fish waste, harmful ammonia and nitrite, into the far less toxic nitrate. To protect this bacteria while cleaning the filter, do not throw away used filter pads until they are absolutely falling apart. Instead, swish them around in a little dechlorinated water to remove any dirt and debris, and put them back.
 B. It is important to protect the beneficial bacteria in the aquarium's filter, because this is what will process the toxins from fish waste, harmful ammonia and nitrite, into the far less toxic nitrate. To protect this bacteria while cleaning the filter, do not throw away used filter pads until they are absolutely falling apart. Instead, swish them around in a little chlorinated water to remove any dirt and debris, and put them back.
Answer: A