Here's a full set of instructions from Unicel:
http://www.unicelfilters.com/pool_ow...rine_users.asp

Again -- though I haven't confirmed it personally -- I have often seen in pool literature statements to the effect that soaking in acid BEFORE washing in soap will permanently 'set' the grease and oils so they cannot be removed. Here's what Unicel says, "WARNING: Failure to remove all oils and cleaning solution before acid soaking will result in a permanent restriction of water flow and cause premature cartridge failure.".

So . . . the bad news is, you may need new cartridges, now. I'd try cleaning them. But if it fails . . . well, now you know why.