hello:
the water temperature now is good(over 28 degree), just add some rock salt just what your mother using for cooking, don't use the table salt it's not good for the fish, and the 2nd step is watch the fish if you found the white spot is less change the water at once because it means the white spot bateria is getting ripe and they leave the fish body to breeding the next generatin at the bottom of the tank, so at that time you change the water that means you can suck the bacteria out of your tank , and then repeat the step once more until the white spot go away, its a kind of method won't hurt the other fish and weeds ,don't always depend on the chemical solution because in a community tank there are other fish not sick.
# the rock salt is only an instrument to make the bacteria getting ripe faster, and the important point is you should catch the time to change the water, every gallon for one tea spoonful is enough.it's very very easy and safe.
