Hi chiahead,
Your Mg is 20 ppm. If you are dosing Mg then slow down, you do not need that much. Only 2-5 ppm is sufficient.
Before you start dosing more TE to fix the problem, try 5ml SS and 5ml PF Solutions. The 8ml SS in 80gall made 0.67:0.22 NO3
O4. This new dosing 5ml SS and 5ml PF makes 0.83:0.14 NO3
O4. This will give you a better chance to increase NO3 in your tank which might be the cause of the deficiency.
Edward
Your Mg is 20 ppm. If you are dosing Mg then slow down, you do not need that much. Only 2-5 ppm is sufficient.
Before you start dosing more TE to fix the problem, try 5ml SS and 5ml PF Solutions. The 8ml SS in 80gall made 0.67:0.22 NO3
Edward