Practical guides on PAR, DLI, CO₂, VPD, reef lighting, smartphone light measurement and the measurement workflows behind AquaHorti tools.
The Blog is organized around questions people actually ask, not around one long chronological list.
See how light, temperature, humidity, VPD and CO₂ changed together across one complete outdoor day.
See the 24-hour measured example →Tomatoes, cucumbers, lettuce, herbs, houseplants and many other crop-specific PAR/DLI articles.
Browse plant-light articles →Understand underwater PAR, spectral choices, acclimation and the lighting decisions behind reef systems.
Start with coral PAR →Why matching a meter at two wavelengths does not prove accurate PPFD measurement across the full PAR band.
Read the accuracy guide →Learn why PAR, PPFD and DLI describe different parts of the plant-light measurement problem.
Learn PAR vs PPFD vs DLI →When a guide shows that you need actual data, continue to the relevant AquaHorti product page.
Browse AquaHorti measurement tools →These articles represent the main knowledge areas of the AquaHorti Blog.
One-minute measurements across a complete outdoor day show how light and the crop environment change together.
Direct research shows why higher light and faster growth can also increase tipburn risk.
Why visual brightness and underwater PAR are not the same lighting question.
Spectral response, calibration, cosine response and the measured spectrum all affect PPFD accuracy.
These selected AquaHorti articles provide practical starting points, measurement context and links to deeper topic-specific guides.
See 1,440 one-minute records from one outdoor day, including PPFD, DLI, temperature, RH, VPD and CO₂.
View real test →A research-based example showing the tradeoff between crop growth, light level and tipburn risk.
Read article →Understand what each measurement means and why one spot reading cannot describe a full day of plant light.
Read article →Learn why coral-level PPFD, placement, spectrum and light history matter more than a universal “sweet spot.”
Read article →Two correct wavelength checks do not demonstrate accurate response across the full 400–700 nm PAR band.
Read article →Research shows how DLI, CO₂, humidity and tipburn interact in a real leafy-green production problem.
Read article →This distinction improves trust for readers and makes technical content easier to use correctly.
When an article gives a number, consider the context around it.
Our technical guides are designed to make the basis of each recommendation clear.
Use the matching product page for specifications, workflow, limitations and purchase options.
Start with the PAR vs PPFD vs DLI fundamentals guide, then review the 24-hour PAR, CO₂ and VPD real-world test, and finally move to a crop-specific guide.
Start with the coral PAR guide, then use the other reef-lighting articles to explore spectrum, acclimation, spread and fixture-control decisions.
No. Smartphone sensors and cameras are designed primarily for phone functions and visible-light imaging. The Blog includes articles explaining where phone-based estimates can help and where dedicated measurements differ.
Use the search box at the top of this page or open the Plant Light Archive to browse crop-specific PAR, DLI, CO₂ and VPD articles.
Search the Blog, browse by topic, or go directly to the relevant measurement tool.