I am treating my 55gallon for ich: temp is 84 and salt is 1 1/2 teaspoon per gallon. Put in the salt over 48 hours and it is all in. The fish all are fine: swimming around happily and eating well. Should I add an airstone to provide extra oxygen?
L.
No, as long as there is some sort of surface agitation going on. A power filter, canister filter with a return at the surface, etc. will give you the oxygen you need. If there is absolutely no surface agitation whatsoever, then yes, you better get an airstone.
Keep an eye on the fish...at 84ºF the dissolved oxygen in the tank is considerably less than the levels at 79ºF, and if the temp creeps a couple of degrees higher (I usually treat at 86ºF myself), the DO will be even less...any signs of the fish gasping (lower DO will effect some fish more quickly than others), and an airstone would be recommended.
If they seem fine then great. As mentioned any surface agitation will most likely be fine. Feed less during this time as the fish will most likely be a little more lethargic.
I don't wait for the fish to show signs the decreased O2 in the higher heat is a problem. If I kick the heat up while fighting ick, the airstones go in.
its not going to hurt so why risk it. i would have added a extra hob or two but air stone should be fine. just like any treatment keep a eye on the fish.