use v6;
my $zmax = 60;    # Maximum depth in your model
my $dz = 0.05;    # Grid spacing in z-direction

loop (my $i=0; $i <= $zmax; $i = $i+$dz) {
    say $i;
}

##</code><code>##

...
3.6
3.65
3.7
3.75
...
59.9
59.95
60