1st grow 250w hps in a cupboard

This is my first grow under a light, trying to do it as cheap and low-key as possible. Thought I would post it on here in case anyone had any tips for me. I will be getting a carbon filter in the next week to help keep the temp and humidity down. I grew the gelato from seed, it germinated on 03/01, I topped it at week 2 and have been low stress training ever since. I am trying to keep the plants small as I am limited on height, that is also the thinking behind using 3 gallon pots The white widow and royal dwarf were given to me by a friend I think they are about 2 weeks older than the gelato. They were started in rockwol and were really root hound when I got them so I think they are a little stunted. I started feeding all the plants on 11/01 and I have been feeding them every week since, increasing the feed ratio slightly. I have been using the biobizz chart for reference but I used biobizz all mix with some added homemade compost so I don’t want to over do it. If anyone has any tips to help out I would really appreciate it as it’s just for a personal stash and would love to get some really tasty product so I don’t have to pay the crazy prices people want to charge in the uk Thanks