Water change plus the salt and temp is important to speed the process. Its not so much the water change, but frequent gravel siphoning that is important. When the cyst falls off the fish it falls to the bottom and then ruptures producing thousands more free swimming parasites. Siphoning the gravel can remove the cysts before the burst. The salt and heat method has worked for me every time over the years. Just keep in mind it will get worse, before it gets better. Eventually all the cysts will fall off and die after they burst. There is some speculation as to if the salt actually kills the free swimming parasite, and that salt is more to aid in gill function during the period of low O2 while the temp is cranked. Either way, it works. Everytime I have tried medications I have lost fish. Never lost any with salt and heat.