choosing the correct submersible pump

[RCB]

noticing that our well pump seems to kick on without any obvious usage - time interval around an hour - thinking either the check valve is leaking or (hopefully not) a leak in my line running from the well to my pressure tank - plan to replace 20 year old Gould with new pump, but am questioning whether I currently have the right size pump for my situation : well is 120 ft deep with a pumping level of 85' - my TDH is 227' with the well producing at 5 GPM according to charts my "peak demand - 7 minute" would be 12 GPM , needing 84 gallons - with the well producing 35 gallons during same time- am using a wx-202 well-x-trol pressure tank which provides 11.3 gallons additional - which makes me short for peak demand - my current pump is a Gould 10GS05422, 2-wire,1/2 hp - was going to replace it with the same size, but have been getting conflicting info saying I should be using the 5 GPM model - haven't had a problem over the years with this pump - any useful info would be appreciated

 

[Danny_G]

Are u using one of the actual submersible pumps which u can buy from a local chandlery?