Hopefully this is a daft enough question to get a simple reply. I have fairly high mains pressure which is good for the shower, but means that the cold water tank in the loft fills fast and quite loudly even with a quiet Fluidmaster fill valve. I would therefore like to slow the fill speed down a little and have purchased an in-line flow reducing valve with a selection of little inserts to test different flow rates. However, I am now wondering if this is the right approach or if I should be using a pressure reducing valve instead! Help!