I am in the process of setting up the fishroom in my new house, and will have a sump room for my main display. I want to have 2 water storeage containers, one RO one salt. and have it set up to automatically change 2% of the water daily. So I need some help on what parts I need. I am guessing some sort of micro processor, flow gage. Or is it possible to use high low flow switches. The main system will have about 300 gallons so I am looking for a 6 gallon water change daily. The sump will have a drain hole in it so the water will overflow out. If the new water is a degree or too cooler than the system it will sink to the bottome of the sump and push the warmer out of the overflow drain. In order to do this there will have to be a shut off to the main system pump to shut it down during the water change. Is any of this possible?