A full-day physics simulation, not a drawing: the environment (PPFD, CO₂, temp, RH → VPD) sets a transpiration rate that drys the substrate back; the crop-steering controller fires shots; each shot mixes feed EC into the pore by the litres applied (shot % × substrate L); when VWC hits field capacity the overshoot runs off and flushes salt out, pulling pore EC toward the feed EC. The white line is VWC, the pink line is pore EC on the right 0–10 axis. Edit any field or drag a glowing handle and the whole day re-solves. Environment seeded live from F2; everything else from number.crop_steering_*.
Live values pulled from F2 on 2026-06-07. Hardware (field capacity, substrate volume, lights) is shared across zones; everything else is per-zone. Next step: write changes back to the number.crop_steering_zone_N_* entities with a confirm step.