Wow. Thats all I can say about this thread. Chemicals being thrown in all over the place.
Setup another temp tank to house the fish in but go buy a simple RO/DI unit. Stop with these chemicals, they don't work. You can use the bacteria booster products since I have heard those work. Use those on the temp tank. You can use the Ammonia and Nitrite absorber products available for filters to help control ammonia and nitrite spikes in the temp tank.
Transfer your fish into the temp tank.
Then, on your large tank. START OVER! No more 10%, 25%, 50%, 75% water changes. Remove ALL the water and clean the tank thoroughly. Clean the filter thoroughly.
Set the tank back up using Ro/DI water (With no chemicals). Chemicals uin your day. The Ammo lock is junk and will make matters worse. Chemicals can cloud your tank heavily. Don't use any salts either. There is no point.
Go buy some ammonia from the grocery store and raise the ammonia levels in the new tank to about 3-4ppm and let it cycle naturally. No chemicals at all.
You shouldn't have all these issues and it seems everything has gotten worse as everyone kept telling you to add all these chemicals. They don't work at all.
Keep an eye on the temp tank to make sure ammonia levels don't reach dangerous levels, if so, do a 25% water change to keep them down. Like said earlier, you can also use ammonia/nitrite absorber filter products available at the pet store that are designed for situations like there.