number of times is less important than how much they get all in all. 3-4 tropical flakes PER DAY should be enough to keep a grown-up guppy going, whether you want to serve that in one helping or divide it into two or three.
when my fish get healthly how many times a month should i clearn them out ( water charge)
Once your tank is settled a water change of 20-25 % once a week will probably be enough, though if you are heavily stocked, and with a heavy waste producer like a pleco, you might be looking at twice a week.