It will not hurt to add all the nutrients, it will just be richer. Occasionally the pH of the water may be too high or too low to be optimum for plant growth. A desirable pH for most plant growth is 6.5 with 6.0 to 7.0 being a good range. If the water source has a different pH, the plant nutrients has a buffer that can change the finished water to 6.5. If you do not have a kit, just go ahead and try the water .
Hydroponic plants use inorganic nutrients and can clean polluted waters.
If the water is polluted with organic matter, it will also need microbes to reduce the organic matter to inorganic plant food. They will usually happen in organic water, or you can add them but adding pond mud to the system. If the water has severe pollutants such as heavy metals or pesticides this many make the plants toxic. Also, some pollutants such as copper, may kill the plants. Poisoned waters should not be used.