Why are these and past autos so small.

Auto.flowers are female... There is no sexing process..Dli should be 20, VPD should be 5. The plants are too dark green, meaning there is too much nitrogen in the soil, all.these factors have stunted the growth. Water with clean water, turn the lights down.. and create airflow.

Terrible genetic. Nothing more..

Forget autos and grow real plants...photoperiod fems! That way you can control the flowering cycle and only once you are satisfied with their size/height. Autos ain't all they're cracked up to be and best left for very experienced growers using top shelf equipment. Not much you can do with these plants now and starting over would probably be the best course of action, unless you are willing to wait another 6-10 weeks to harvest a couple of bowl fulls.

Autoflowers kinda suck, unless you benefit greatly from their non-photoperiod flower trigger. They are less consistent in many aspects and can be under-sized. You'll get more consistent growth with soilless/hydro context than soil. This cna make a big difference with an autoflower that is on a short trigger. Need to maximize the vege growth you get because you have no control over when it ends and it ends relatively fast. Looks like you have a good amount of drainage amendments and that helps a great deal. as long as some internode growth is occuring, it's not too much light... if you notice that the stem between nodes does not develop over time, it's possible you are stunting them. Sometimes this takes a while fromt he time of 'too much light' and actually seeing ramifications.. can also take a while to bounce back to normal growth. 32dli should not do that, but if yousing a phone app given likely error% of measurement (conversion from lux is what is actually occurring) it is still possible. good watering habits: make sure entire thing get saturated with minimal runoff (unles trying to mitigate a toxicity in substrate). Wait for top 1/2-1" to dry and repeat. Frequency of added fertilizer depends on how concentrated it is. How depleted your soil's nutrient charge has become over time is another part of that equation, too. Looks a little overfed. if you've been fertilizing, maybe back off a bit.. lower dose or add another water-only irrigation between.