I doubt it matters if you add them or not.
I have a prizm - here's how I started. Turn it on, get the water flowing through, but keep it turned down low, you don't want to flood your house with wet semi foam. Now accept nothing will happen for a couple of days. You need to get the plastic dirty, and to allow the plastic to release anything on it.
Now , 2 or 3 days later, start to notch up the water flow. You should see bubbles appearing in greater numbers as the water flow increases. There is a junction beween the main body of the thing, and the neck - I let my foam start to sit a couple of millimetres down from that. Now leave it here for a day or so and see if any foam appears. If nothing foams notch up the water flow a little bit, if it's too watery and not dark notch it down. Initially leave it at least an hour between changes as these things are not easy to adjust, and easy to overdo it.
Incidentally the surface is a real pain unless you have an autotopup