I have a 400B HOB filter on one of my tanks. The tank is for a turtle so it's not filled all the way to the top ( it's a big tank ). Problem I am having is the loud noise from the water falling from the HOB into the tank. The tank is in our tv room so I would like to make it quieter. I was thinking of trimming of the little lip on the overflow return area and then gluing either plexi glass or acrylic to the back of the existing return that way the water can trickle down that to the proper height of my water so it's quiet. My question is what material should I use far as acrylic of plexi and what thickness? Also what to use for glue? And lastly do you think this will make it silent?