Collected  water and treatment to re use for drip irrigation inside the Solar glass greenhouse

We have a solar glass greenhouse project with 9 acres of roof water to be collected and stored in an open rain water harvesting pond. We wish to use this collected  water and treat to re use for drip irrigation inside the Solar glass greenhouse. Please suggest the size of rain water harvesting pond based on 9 acre roof and considering the rain fall data For the place "Haridwar" in Uttarakhand state in India and also in the place "Kanpur" in Uttarpradesh. The treatment facility can be portable or fixed. Can we use the PART OF large rain water harvesting pond as a FISH POND? If yes, please submit the proposal to : praveenkulkarni@kknesar.com Are there proven technology with low cost machines to CONVERT AIR TO WATER. The solar power generated from the roof our solar glass GH can be used for running these AIR TO WATER MACHINES. Please submit the offer with energy needed to run these machines with capacity. Send the offer to: praveenkulkarni@kknesar.com