For every meter you raise it I think the pressure increase by 0.1 bar
You can calculate static pressure in the ibc by using the formula p=pgh.
P= density (1000kg/m3 for water)
G = acceleration which normally is 9.81 m/s2
H = height in metres
So Pressure = (1000kg/m3) (9.81ms2) (1)
= 9.81kpa
10kpa = 0.1 bar
This will give you the results above atmosphere which is approx 1 bar (14.4psi)
I follow your logic but my understanding and experience is every 10 m head of water is 1 bar pressure. From our storage tank to bottom of hill is 100m we had to put in a pressure reducer half way down as we were at 10bar at the bottom your maths would have put me at 100 bar or 1500psi