Hello ! Well you should not let them in the same pot , autos have a short life time to grow well and that setup will make your 3 babies roots fight for the space in the pot. However if you still wanna keep them in the same pot then you should start some lst soon ( wait for one more node at least). I can also see that you'r not using any ec/ppm meter and you'r in coco so you will soon need one to know what is the nutrient level in you feeding , and in your water runoff : in coco you should check the runoff EC and PH to spot any ph fluctuation and a too high amount of nutrients. I hope it will help you 😁👍