remove them to give your plant the strength to keep going.
if you give your plants the things it likes as mentioned above, then it will bloom it's heart out for you and will bloom all year round.
sometimes i like to start new ones for family or friends. you can do this by removing a leaf and poking a toothpick through it to hold it up, put it in a glass of water with the leaf base just in the water and place it in a sunny window for a week or so. when you have a few roots started, plant your new baby plant in the same kind of pot 