I'm a homeowner who has put in my own system but I called a professional to extend the system to the back and add drip irrigation since I've been inudated with other projects. This guy has "irrigation" is in his company name and has been doing it for 25 years he claims. When I looked at his wiring job he used non-grease caps which I had to do back and fix. But anyway my main question is he didn't put any mesh filters on the drip valves. He claims they aren't needed. I think they are. Its city water. What do you recommend?