Feeding phytoplankton question

[Oilers]

I've just picked up some copepods at a local LFS today and was told that I need to feed the copepods phytoplankton as well. I have read that I need to turn off my return pump and skimmer during feeding. Is that true? Also, how much do I need to feed? I was told to feed 3 times a week at about 5 mL for every 10 gallons. I just need some confirmation if that's correct since I don't want to overfeed which can cause an algae bloom in my tank. Thanks a bunch.