Hi
@Smallbutstrongdwarf! I would recommend to use powder fertilizers. Liquid fertilizers are much more difficult to manipulate, and the plastic bottles tend to accumulate salts. Daily hygiene + heat + light may degrade the liquid fertilizers. Powder fertilizers on the other hand are easy to manipulate (you just need an accurate scale), they are less sensitive to heat&light, are easy to store (in jars) and will remain unspoiled for a long time. I've had great results with the following brands: "GreenleafNutrients" & "Mr B's green trees". Now about your small space, you must use LST methods to control the plant's height otherwise you plant will certainly become bigger than your box. Hope this will help, keep us up-to-date and happy growing 👊