Most of the time I agree dips are useless and stressful. IMO
it is possible to offer some relief, although I would only consider if the fish was heavily covered in it AND I was going away for a week. But I agree it is still risky and questionable at best and by no means a cure (FW
cannot get the parasite deep in the skin). If the fish is not too badly covered with ICH, I would just do a water change or two, make sure the water parameters are perfect, and get some garlic to mix with the food and maybe some vitamins to boost the immune system. They should survive till you get back and treat. As you stated, managing a new qt
/ med tank can be very involving and I would not leave that to someone else. But I would start cycling the qt
tank (if you decide to treat when you get back). Just put liverock, a filter or stocking full of sand in there and a powerhead, set temp to 80-85 F.
Lowering the salinity in the main tank (to 12-14ppt) is a consideration under extreme situations like this also. Obviously, this would depend on how many inverts you have in there. Oh, and just in case you are tempted, stay far away from so called "reef safe" ICH cures. They will do nothing but pollute your system. Good luck with it and let us know what you decide to do...