Do any cannabis strains attain 30% THC? [I don't think any such strains exist. Maybe, could get to 30% with some metabolic and/or genetic modifications. But no one seems to be doing such strain modifications, at least in terms of offering seeds for general sale. 'Breeders' (seed sellers) are still just playing with pollen and cuttings as clones, doing things much the same as 100+ years ago, not working with more precision at the metabolite, gene, protein, or even cellular level. For example, why aren't breeder companies using CRISP-R (turns gene/protein expression on/off, no genetic modification involved) to boost or decrease desired cannabinoids, terpenes and other plant constituents?]
U.S.-based seed sources that offer multiple auto breeder product lines include DC Seed Exchange and Oregon Elite Seeds, both of which I believe have sponsored sections here on AFN. And don't forget you can buy direct from the Mephisto US outlet, with Mephisto also having a presence here on AFN.