>, agricultural distribution pipes are matt black PVC

Really PVC?! - Here we only use PE in the pipes
(Much longer life in the sun, better freeze survival, and no piosonous to
burn at life end)


If it is drip irrigation you probably want to add nutrition too.
There are theese relatively cheep water flow driven nutrition pumps.
Theese are pulsating cylinter type pumps, made of plastic.
If possible to add a magnet on the moving part, and a hall sensor at the
case, you will have one pulse per x volume of water!

Water Supply --> Filter --> Nutrition pump --> Valves
                               ^    Magnet        |       |       |
                              /       :           v       v       v
                             /        :           Filters
                            /         :           |       |       |
                Nutrition tank  Magnetic sensor

/Morgan
        Morgan Olsson                   ph  +46(0)414 70741
        MORGANS REGLERTEKNIK            fax +46(0)414 70331
        H€LLEKS           (in A-Z letters: "HALLEKAS")
        SE-277 35 KIVIK, SWEDEN               mrt@iname.com
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