@hippy4life see thats the whole thing with the TDS. It really depends on the enrichments in your soil. You need to look at what the nutrients call for on their feeding chart and use that in coordination with the runoff you are getting from your soil.
You are on week 4 of the FF Feeding schedule and the TDS calls for 1750-2100
If you give plain pH water today and the TDS runoff is say 2200 ppm you would not want to give any nutrients until the runoff number is less than the recommended TDS value established by your nutrients.
If you give plain pH water today and the TDS runoff is say 1100 ppm you would want to give a feeding at the next time of TDS of approx 800 ppm
The important thing to do is check the TDS of your nutrient mix and then the runoff as needed during your grow.