I didn't manage to flush my res yesterday as I had other duties in the garden to attend to. I did however check the pH and EC levels giving 6.1/1.2

This morning I went in before lights out and scrubbed the system and drained the res. I replenished with pH 5.6 water without any additives and left the system running. I will do a second drain and replenish shortly then apply a full mix of all addatives to EC1.2-1.4.

I have chronic signs of over fert again due to the EC2.2 occuring for a second time... I will take some pix shortly and get them posted.