You can try Tisbe copepods.
Tisbe are small, benthic dwelling pods which also eat detritus as well as algaes. They are "easy" and most likely will self propagate in your tank, sump or refugium ( if they dont already exist there).
Tigger pods are large benthic(bottom, surface) dwelling pods and have been grown outside without any addition of algaes, just eating any detritus which falls into their container( ie leaves, bugs etc..) Tigger pods will also eat other pods and have been know to self propagate in the tank, sump or refugium.
What type of Phyto are you looking at? Nannochloropsis, Tetraselmis, Isochrysis.
The culture of algae is easy if you can devote the time, effort and space needed to succeed. However If these are the two you are looking at and you are just looking to add them to your food chain then some of the prepaired algae pastes would due.