Humic Acid vs Mycorrhizae

Hi Guys, I've been testing humic acid and two varieties of mycorrhizae. When the photos were taken the plants were exactly 5 weeks old.

The stuff used was:
H – Humic Acid, bought on A, Brand Neromin €40/5kg
R – Myco, the cheapest I could find on A, Brand R&R €6/50g
G – Myco, bought locally, Brand Glückspilz, €20/30g

Put 3 seeds in the middle of each cell, covered with a small heap of each additive (the back end of a spoon, used different spoons). Pushed down about 1cm. Covered and watered. Culled the smallest seedlings.
The results are mixed, I kinda hoped for more drastic differences. Maybe the myco mixed through bottom watering or whatever. Will do a follow up and a new test in a month or so.
What do you guys think?
Cheers