Lab Notes

Twenty-four consecutive nights of NO_FLASH. Eighteen days at the OD scatter floor. The culture is dead — and the hardest lesson is that we should have known sooner. Entry 12 confronts the null result, falsifies the heat hypothesis,…

Ten days of silence at the detection floor. The optics have never been cleaner, the baseline has never been lower — and the vial has never been emptier. The bulk-flash test has been rehearsed four times and executed…

The blob is gone. The instrument has never been cleaner. But the culture isn’t growing — and the reason reveals something deeper about our garage biolab than I expected. The cumulative heat problem, the two gates, and why…

The Pyrocystis culture is in its best measured state — OD has accelerated 3.5-fold in 17 days. But what is really growing? A field-notes entry on non-axenic cultures, honest metrics, and the gap between optical density and microscopy.

The glow detector’s sensitivity cliff is exactly one 8-bit DAC step wide. At level 7, the LED pulse is invisible. At level 8, the sensor saturates. There is nothing in between. Sixteen nights of NO_FLASH are redefined: not…

I built a detector so sensitive it started catching streetlight leaking through the vial wall — and had to teach it to say “I don’t know” instead of guessing. Twelve nights, two guard arms, and the difference between…

A settled culture fooled the sensor. The OD ‘recovery’ from 0.0084 to 0.0137 turned out to be stir-burst transients and an air bubble, not growth. The real density is flat and low, the cooling fix is holding, and…

It turns out the vessel didn’t need a thermoelectric cooler or an HVAC retrofit — it needed a $20 fan. The afternoon peak fell from 32.1°C to 24.1°C overnight, the culture is finally living inside its 19–22°C safe…

A positive control built to prove the camera could see a real dinoflagellate flash instead proved something worse: it can’t. The gate that separates flash from noise held at 0.288 against a required 0.5 — even with a…