First Grow - Trying to F1 Autos

Days 64-70 July 30-Aug 5 - Bad nutrient burn and fully flushed the soil (crazy high ppm in the runoff Day 65 July 31 noticed significant nutrient butn. flushing plant 3 with 2.5l of 6.5ph 143ppm water... Runoff was 7ph 1737ppm. Runoff (fed 3l) plant 2 was 6.98ph 2641ppm. Runoff (fed 3l) plant 1 7.28ph 2643ppm Day 67 Aug 2 continuing flush. Water ph to 6.1 136ppm plant 3 fed 4l run off 7.1ph 1737ppm fed 3 l more pH still high PPM drop to 900 7.24ph... plant 2 fed 2 gallons through until ppm 883 7.19ph... plant 1 fed 2 gallons of 6.2ph... runoff eventually 786ppm 7.6ph Day 68 Aug 3 plant 1 smells strongly like terps Day 70 Aug 5 plants are very yellow, mixing nutes lightly 1.25ml floramicro 3.75ml florabloom 5.95ph 300ppm trying to keep ppm down