Hey 4f1hmi; if you look
at his website he is using Flourish products, which lead me to believe that he has also a Flourish substrate; my guess is that he is using Flourite Red, but i am not sure.
By looking at the nutrients he doses in his 37 gallon tank i derived the PPMs he adds daily by using Seachem's website:
Flourish Trace: 5ml/daily
Flourish Excel: 20ml/daily
Flourish Phosphate: 25ml/daily (adds 0.84ppm PO4)
Flourish Potassium: 20ml/daily (adds 6.49ppm SO4)
Flourish Nitrate: 10ml/daily (adds 1.08ppm NO3)
Flourish Iron: 15ml/daily (adds 0.22ppm FE2)