MY HYDRO GARDEN??

Hi there am using an nft system with rockwool as my medium, all auto flowers, they germinated very well but got off to bad start they were tiny and yellow nearly all over, I started giving them feed week ago 1/4 the strength to start off, in just over week they have taken off, the yellow has almost fully gone thankfully! Ive them under a 400w hps orange sodiun light 18/6, keeping the temp max of 26c and min 16c when lights r off, there in my nft system 3 weeks now, my question is now that there fully up and running can anyone give me some advice on the next step when they start grow lot bigger this is my first doing hydro so unsure what to do when it comes to tying and chopping my plants in the nft??

I have not grown auto's yet but I don't think you have much of that to worry about. Maybe one bamboo stake to hold them up. Do some searches on auto flower. your's are already starting to flower and will not get big from what I have seen. maybe quater once each or alittle more.
Kick your feed up if you haven't I do ebb and flow now very simalar.