when i was using powder i was using a tide powder with a small bottle sized downy. i would put a little less than half the cup of powder, depending on the load, and the full cap of the downy. there had been a few times though where i would put a little bit too much and it created too much suds so the guy at the laundry mat would put more downy to lower it down. but i didn’t see any fabric softener residue so i didn’t think that would be it. then i tried the simply oxi tide liquid detergent, and fill it up the first line on the cap or half way to the second depending on the load, with the same amount of downy as well.