No, do not use table salt. Table salt has iodine in it. Rock salt can be used but not regular Morton's type table salt. Salt is not a treatment for fungus. I recommend getting Pimafix and begin treating with that.
Actually, I stand corrected. I apologize. "The levels of iodide added to table salt are so small that any water-living vertebrate would be pickled in brine well before toxic concentrations of iodine/iodide could be reached, so that particular urban myth is without foundation. In fact, a number of our tank inhabitants need iodine- most crustaceans have a significant demand for the material, and a number of fish can develop goiter in captivity from the lack of iodine- African Rift Lake fish seem especially prone to this. The often-discussed toxicity of iodine could be considered urban myth #1."
Manual of Fish Health by Dr. Chris Andrews, Adrian Exell, and Dr. Neville Carrington recommend the use of cooking salt or aquarium but NOT table salt
A - Z of Tropical Fish Diseases and Health Problems by Burgess, Bailey, and Exell State that it is important not to use domestic table salt, as it contains additives that may prove toxic. Block cooking salt or crystallized sea salt, but preferably aquarium salt are all considered safe.
Tropical Fishlopedia A Complete Guide to Fish Care by Mary Bailey and Peter Burgess It is important to use the correct type of salt to treat the aquarium. The first choice is aquarium salt, then block cooking salt and crystallized sea salt are technically safe. Standard Table Salt is not appropriate as it contains "potentially toxic additives".
I would be hesitant to use table salt based on the statements above.