Apparently not providing information is a tradition around here.
Make sure you have checked your external filters and they are reasonably clean, they should not be spewing junk, if they are they need to be cleaned (but not over cleaned).
Assuming the filters look fine and nothing smells bad, then most likely a bacterial bloom, do not worry about it, the micro-critters are just working to colonize your tank and/or filters.
Assuming your tank has been cycled for a while there probably was some disturbance, or someone tossed a handful of sugar (or a couple of hard candies). A trick some old guys use to care for fry is to add some sugar around anticipated hatch time.
Assuming your tank was well cycled it is highly unlikely water changes caused any problems, frankly water changes are the solution, not the problem. With two canister filters especially.
A water softener will add a little Sodium or Potassium (depending on what you use to backwash) and obviously reduce general hardness (GH), but should not be a significant problem.
I agree with Diana, I would not use Ammonia chips, you have filters, add plants if anything.