OK I think I am finally up to speed. So the 700 gallon reservoir is the amount stored in the well between 33' and 500'. If I use the 33' static level and look at the pressure the 5GS10 can build, there will be 230 PSI on the inlet to the CSV and all the pipe prior to the CSV. This is a little more pressure than we like for the CSV1A. 230 PSI coming into the CSV1A and 50 PSI going out will be a differential pressure of 180 PSI. While the CSV1A will work with that much differential pressure, we do not recommend more than 125 PSI differential. The higher the differential pressure the sooner it will wear out the CSV1A.

With systems that have high differential pressure like this we use two CSV1A valves and stair step the pressure down. The first CSV1A would be set at 140 PSI, and the second CSV1A would be set at 50 PSI. This way the differential pressure is split between the two valves. Both CSV1A valves will last a long time with only 90 PSI differential on each.

However, having said that, you only have a 5 GPM pump. The CSV will only work between 1 and 5 GPM. It is not nearly as useful as it would be if you had a 10-25 GPM pump. With only a 5 GPM pump, it only takes a 44 gallon size pressure tank (10 gallons of draw) to get long run times with a 5 GPM pump.

I would love to sell you a Cycle Stop Valve. But this is one of those times when just a regular pressure tank might be best.