Having the water (or soup) boiling when you first add the matzo balls is fine but then you want to partiall cover the pot and reduce the heat to about medium.
Give this a shot (note the different proportions of meal vs. egg vs. oil/fat vs. water):
4 eggs
5 T butter or margarine, melted--or oil
3/4 t salt
1/4 t black pepper
pnch white pepper
1/2 c finely minced fresh parsley (do not use dried)
1 T finely minced fresh sage or thyme leaves (or 1 t of either, dried, or a mix of both)
1 1/4 c matzo meal
1/2 c seltzer or club soda
Whisk the eggs till very frothy then add the melted fat or oil, the salt, black and white pepper, whisk briefly, then add the herbs and whisk briiefly to combine.
Gradually add the matzo meal then stir in the seltzer or club soda. Cover and chill till firm, at least 2 hours or up to 4 or 5.
Form with wet hands as you know. Cook as noted above (they can take as long as an hour for small ones). You can pull them out when done, draining well, and hold at room temp for a couple hours, reheating when needed, or you can let them cool then fridge them, covered, for a day. I wouldn't go longer though.