I use both phyto and rotifers, usually at once, twice a week to feed my paly. They seem to eat it and I assume it helps growth, though I haven't recorded or looked any results.
I voted for all three. I don't actually use any of them, but Jennifer uses a combination of the three in the little tank. Since the little tank is plumbed into our system all the tanks get some.
If she gets to crazy with it I start to see some excess algae in the tanks. Then I have to complain about her abusing it and temporarily revoke her feeding rights.