Hello - I have low flow at a number of fixtures throughout my house. Today I embarked on figureing out why. Here's what I have in the order flow: city water comes into the basement, then a watts 25aub regulator, then a water softener, then to all my fixtures. My house is 20 years old and is a 2 story. I measured the water pressure at various fixtures today and it was 100 psig. For example, at a shower head it measured 100 psig, then when I turned on the sink next to the showermthe pressure would fall to 60 psig. After shutting the sink off it would slowly rise back up to 100 psig. So, it seems I must have a bad regulator, but would that restrict flow? When I took the gauge off this shower head and filled a gallon container (straight from the pipe, shower head not attached) it took 40 seconds. No other fixtures in the house were on. So my flow rate is 1.5 gpm out of a 1/2 inch pipe. This is very low. The only other thing I can think of is the water softener. Would it restrict the flow? I painstakingly tracked the copper piping through my house and there weren't any other valves or regulators installed. I'm befuddled, any suggestions are appreciated. Thanks!