Then the soil mix for the trays
Their aint no ingredients off their soil mix on the site.

Hate that.
Mine both supermarket, all are so called Bio. One is more or less more Bio then the other.
But technichally they are both not, just compliant with Law regarding putting the name Bio on soil.
They use mostly Peat, wich wil destroy nature and release the gasses heating up the earth.
The better one uses ecofriendly harvested Peat.
Some add wood or Pine wood leftovers, which pesonally is something if to big means sifting out big parts.
Irritating, lucky its brand/ batch related. Milled would be prefeable.
The better one i have now, far from perfect as tests showed most were lacking on the food appartment.
Etiket vs reality. overal scored good. They where all save all Bio [and no relation between price and quality !.
But i ll alway add
Lavastarch when repotting with it. SR mineral suplement,
100 % BIO. And if available Coco-Peat.
This 'best one' garden Peat, Ligima [no clue what it is neither to found ?], Peat, Coco and Compost [the death degenrative kind],
80 % Plantsourced nutrients and natural Phosphate and Bacillo Sp.
The other no Ligima, Cocos/ Compost or Bacillus. And the nutrients '
100 % BIO' [yeah right, and i can t write]
From mineral [milled unnamed rocks/ moutains] and organic sources [parts of death animal/ fisch and their shit?] .
For Weed I would go for at least a detailed and verified ingredient list. Preferably containing all already mentioned.
Real BIO and no Peat. Besides the Bacillus some Mycorhizea would be good. Regenerating living compost [not meaning Wurms ed]
Maybe some Sheep Wool, Wurm poo and Dry Seaweed to.
Making your own mix re-using and re-vitalizing used soil the ultimate goal. Circulair if possible.