prob best way to handle that is tear down the tank for a couple of hours.
remove all lr, fishies, etc from the tank and put them in buckets w/heaters and power heads.
drain the tank but dont throw out the old water! reuse it!
scoop all the CC out and replace with LS, then put the water back in, turn pump and heater on and let it run till temp is up to normal, then put everything else back in. Yes...I speak from experience!
I will never use CC again!