I also use biobizz lightmix. It won't see you through a grow to finish without any additions, but gets them off to a great start.
If your looking for minimal inputs, you could try a simple canna range. Canna Start (for early seedling), Canna Vega (for veg) and Canna Flores (for flower) like this thread
https://www.autoflower.org/threads/sweet-trainwreck-tickets-please.79261/
If you want to go organic and water only, you could look into biotabs which will break down over time (although in my experience, you would still want additions to get the best out of your plant). Like in thie thread
https://www.autoflower.org/threads/crystal-candy-with-biotabs-gn-telos.65191/
Using PK during flower to fatten and tighten the buds is a good idea. I use Dutchpro explode, or if going organic BioPk from biotabs.
Hope this helps
Blue ^_^