Crystal-like Water Conditioner, Sodium thiosulphate Options

[d_golem]

Just bought this tub of crystal-like water conditioner (cheaper than any of the liquid ones). No info whatsoever on the tub about what it made of, but after a brief search in this forum, I think its sodium thiosulphate. I also read some negative things about using it, namely the ammonia released after neutralising chloramine, and about AC to absorb the ammonia after de-chlorinating.
So if I just put a bag of AC in (or how else u use AC? never use one before) it'll be ok?

thx