Better to "cure" newly aquired LR in a rubbermaid container with a PH for a few days, rather than jepordize livestock, for future reference.
The problem with using those products is that when you start testing for ammonia after using it, you get false readings. I'd continue with the water changes if at all possible. If you have some more PHs that aren't in use, add some to the tank temporarily.
Don't add anything now until your tank has been completely stable for at least a mo.