I don´t know how advanced you are, but it is a good idea to germinate the seeds in smaller pots (they grow faster that way, and you go up in size during veg). I don´t know how “hot” that soil mix is, but usually for a 1/1/1 mix of peat/perlite/humus+compost you also ammend with some kelp, neem meal, crab shell meal and gypsum. These are not expensive as guano and other stuff and go a long way.
If that White Shark is mychorrizae, you don´t need to mix it with the soil. Just pust some a bit below where you plant the seed, it spreads with the roots. All mychos not in contact with roots are wasted.
You can see some discussion about this on this thread:
I wish you success with your grows!