If they are still eating I wouldn't get too stressed just yet, mine have gone through a few bouts {usually when they get stressed}but have come back no problem. Garlic {liquid} is good and I don't think I would try to adjust water or temp to drastically as that can stress them out as well, If your water parameters are within spec's I would probably just wait and observe. If they are not eating then I would be real concerned, make sure you are giving them some Nori as well. Good luck.
