How to not show on the terminal my program - bash

Question

I use GROMACS. I think about how can I make my script faster.
This is my script
#!/bin/bash
number=1
for var1 in {1095000..1100000}
do
gmx hbond -f luteina_wertykalna_1095_1100.xtc -s sim_prz_lut_d.tpr -n kuba_index_sim_prz_lut_d.ndx -hbn eq3_test_$number.ndx -r 0.4 -contact yes -b $var1 -e $var1 <<EOF
8 45
EOF
number=$((number+1))
done
My script makes 5000 files and it shows on the screen program GROMACS and wants me to choose two numbers (that is why I use <<EOF 8 45 EOF to make this automatically for every file).
But I heard that showing something on the screen takes time, so how to not showing gromacs program in the terminal?
I try to use '>' but still, I see most part of the program (I do not see the part when I should choose the number
#!/bin/bash
number=1
for var1 in {1095000..1100000}
do
gmx hbond >/dev/null -f luteina_wertykalna_1095_1100.xtc -s sim_prz_lut_d.tpr -n kuba_index_sim_prz_lut_d.ndx -hbn eq3_test_$number.ndx -r 0.4 -contact yes -b $var1 -e $var1 >/dev/null <<EOF
8 45
EOF
>/dev/null
number=$((number+1))
done

Answer 1

Terminals have 3 file descriptors by default:
Standard input, a.k.a. stdin
Standard output, a.k.a. stdout
Standard error, a.k.a. stderr
When redirecting >/dev/null it actually redirects the standard output to /dev/null, which is strictly equivalent to 1>/dev/null
However the program may also output to the standard error, in which case you may want to add 2>/dev/null to suppress stderr messages:
gmx hbond >/dev/null 2>/dev/null -f luteina_wertykalna_1095_1100.xtc -s sim_prz_lut_d.tpr -n kuba_index_sim_prz_lut_d.ndx -hbn eq3_test_$number.ndx -r 0.4 -contact yes -b $var1 -e $var1
In Bash you may use &> to redirect both stdout and stderr at the same time:
gmx hbond &>/dev/null -f luteina_wertykalna_1095_1100.xtc -s sim_prz_lut_d.tpr -n kuba_index_sim_prz_lut_d.ndx -hbn eq3_test_$number.ndx -r 0.4 -contact yes -b $var1 -e $var1