Subtract a function from a histogram

Dear friends,
I have created a TH1F histogram and I used a “gaus” function (TF1) to fit it and it works.
My problem is that I would like to subtract the gaussian from the histogram. If it is not possible, how could I create an identical histogram and do the same task instead?

Thank you in advance for your help,
Giorgos

use the TH1 function

virtual void Add(TF1 *h1, Double_t c1=1, Option_t *option=""); with c1=-1

Rene