how to control tank pH

[melegio]

Hi,
I need some Help to control my the pH in my marine tank.
During the night my pH is too low (7.8-7.9). For this reason I would like to rise the pH by adding soda to my tank with a dosing pump. I have a profilux 3 but I do not how to drive my dosing pump. Please, Can someone help me.
thank you
Giovanni

[Matthias]

simple:

1. set nominal value of the pH sensor, e.g. 7.6
2. assign the function "pH 1 control upwards" to the socket which corresponds to the dosing pump