Adding a UVB bar to the tent is one of the few tricks with research behind it, though the effect on THC is modest and dose dependent. Too much UV burns leaves and slows growth, and the studies showing gains used measured exposure, not a reptile lamp hung wherever it fit. Before buying I read the summary of the published trials on https://potentthcseeds.com, which is more sober than the vendors selling the bars. My result was maybe a point or two, hard to separate from variation between THC seeds.
