Hey everyone, I am trying to start my first 5.5 gallon aquarium with neon tetras/fancy guppies. I saw a rule that said to look for a gph that is 3-5 times the number of gallons, 16.5-27.5 gph. I'm not sure what this really means or what filters would work. I saw alot of good reviews for the tetra whisper 3i and 10i in tank filters. Would I be okay with the whisper 3i (20gph) or would the fish I want need a higher current flow? I'm not sure how much of a flow would be best for these small tropical fish and I dont want one too weak or too strong. If you know of other filters please do tell. Thank you!!!!