They all stopped growing

Check the ph in the dirt with a slurry test and adjust the water ph to the dirt ph and no nutrients until they start new foliage growth !

Biobizz lightmix soil is ok for two first weeks after that start fending any preffered nutes ,but I would avoid small plastic 6L pots unless airpots etc…iam using fabric pots 12L with biobizz productsall good so far , also it’s look like defficiency of phosporus.

Man it looks like phosphorus deficiency in some pics.. I’m not familiar with biobizz but I thought the light mix had no nutrients basically? It also looks like it could be severe over feeding. Other thing to consider is micronutrients.. are your feeds containing all the necessary micronutrients? Kinda looks like a zinc deficiency too. Probably wasn’t much help but some things to consider. Also, check run off EC/PPM and pH.. that should give you a huge clue as to if it’s building up salts and locking out

How long does your soil take to dry, could be a little root rot might want to take them out those pots clean up the outside of the root zone and plant them in bigger pots , maybe add a little more aeration to your soil. How long have they been in those containers