Rent by the room and fair housing laws

[William Ring]

I currently have a 3 bed 2 bath house hack where I (23M) live in the master and found roommates (22M and 23M) through matching apps to rent out the other two rooms and share a bathroom with each other. I am wondering how to make sure I can rent to a male around the same age when I move out because it has been expressed from both tenant/roommates that they only want to live with young professional males. For anyone who has rented by the room, how do you make sure you don't get caught on the wrong end of a fair housing lawsuit? I know while living in a place you can chose whoever you want for whatever reason, but when I move out, I need to get a male roommate for my current roommates to stay.