As you've noticed, it can be a minefield. Your tanks and filter should be adequate for what you want to keep tell us a bit about the existing set up (tank size (L x W x H) type and make of filter, lighting, type of fish you're keeping, any plants, rocks etc) and then people will be better equipped to help.
You could join a fish forum such as
http://www.theaquaticroom.com/forum/index.php people will bend over backwards to help you.
As for, feeding...just once a day, again, depending on the type and amount of fish you keep.
Good luck and keep asking the questions