Test water immediately for nitrate, nitrite, and ammonia. When you added water did you use safe or something to remove chlorine? Was water added the same temperature as the tank? Hot water can make the tank hazy. What is the temperature at right now?
Do a 75% water change right now. You should have done a water change instead of just add water. AND FILL IT ALL THE WAY UP!
Do you have surface agitation from filter or air stone?
This tank looks like it has not had a water change in quite some time and the water is low due to evaporation. Water changes should be done once a week and at least 50%
I don't know what size tank this is, but it looks small for all the large fish in this tank.
Please answer all questions and we can help you.