Very helpful that Katty advised that the Edge filter is really just an AC model 20 because the AC20 is identical to my old AC-Mini that I run on a quarantine tank. I think I just replaced the carbon bag with a bag of ceramic lumps (probably the thing they call biomax.) Its been fine. The sponge in that filter is going to do most of the work so whatever you've added today will probably be fine.
Yes, that filter and more or less all HOB (Hang on Back) filters are going to make waterfall noise (that's one of the things that make external cannister filters nicer when you get a bigger tank.) We just live with the noise our little one makes, its less after water changes when the top level is higher. Be careful if you experiment with attemps to quiet the flowing water, many beginners don't realize how easy it is to have water get accidently directed out of the tank or "wicked" out by some object that bridges the tank wall - you have to be very careful about this sort of thing.
~~waterdrop~~