Let \( x \) be the number of comic books on each shelf. Since there are 5 shelves, the total number of comic books in the collection can be expressed as \( 5x \).
According to the problem, Jose's father adds 20 comic books to the bottom shelf, resulting in that shelf containing 125 books. Thus, we can set up the following equation for the bottom shelf:
\[ x + 20 = 125 \]
Now, we can solve for \( x \):
\[ x = 125 - 20 \] \[ x = 105 \]
Now that we know there are 105 books on each shelf, we can find the total number of books in the collection:
\[ \text{Total books} = 5x = 5 \times 105 = 525 \]
Therefore, the total number of comic books in Jose's collection is \(\boxed{525}\).