Need experts for filter selection and sump & OHT maintenance in Bangalore, Karnataka

I live in Bangalore (HRBR layout). Our source of water is Corporation (cavery water) and borewell both of which gets stored in Underground sump from where it gets pumped to the overhead tanks. I need help to fix water filters at the source of the underground sump and at the inlet to the overhead tank to stop the visible dirt/sand which gets into the overhead tank.  Please help me find good quality water filters which can be fixed.

 Also need to know if there is any professional team/group which would hlep me with periodic cleaning of both underground sump and the overhead tank.

Vardarajan G