Everyone talks about nutrient ratios, but nobody measures the EC spike caused by simple surface evaporation in sub-200ml glass vessels. I ran a test on my miniature schefflera setup with an industrial-grade Bluelab probe calibrated weekly. Within 14 hours under a 15W array, water loss shifted the EC from 1.2 to 2.4 mS/cm. That is enough osmotic pressure to roast the root hairs on anything delicate. Reminds me of when I built my first custom water loop for a dual-Xeon rig in 2011 and neglected reservoir volume ratios. Instant thermal throttling. You basically need a micro-dosing auto top-off or you are just slowly pickling your mini trees 📉.