Kick Ich as well as other so-called reef -safe products do not work. It is a waste of time. money and is counter-productive. They use buzz words such as reef-safe, organic, all natural, etc. They rpovide no evidence of working and many do not even bother lsiting the ingredients. Most of these products are nothing more than a slime coat additive in colored water. They can damage your water quality and actually harm inverts.
The only proven additive effective against ich is copper which will also kill all inverts. . THese so-called reef safe products claim to be effective against ich and will not harm all the other inverts. How can this be...one invert is killed and all others spared? it defies logic based on known science today.
Remove all the fish and treat with hypo. Copper can cause internal damage to fish as well as other problems short and long-term. Copper is like chemotherapy for fish.
Since you asked, the appropriate way to perform a freshwater dip is to match the system ph and temp. Leave the animal in there for several minutes and monitor for signs of stress.
Performing a freshwater dip then placing the animal back in the diseased tank will do little in combatting the disease.