Boas
A referência para o led é mesmo o PAR. Os lumens são um indicativo mas o que conta é mesmo o PAR.
Por exemplo: a calha Chihiros A1201 tem 9700 lumens, mas um PAR a 50cm de 47.8 mas a calha da ADA (RGB) tem "apenas" 3000 lumens mas tem um PAR a 50cm de 177!
"Plant biologists define light in the 400nm to 700nm spectral region as “photosynthetically available radiation,” or PAR. The unit for measuring PAR, micro-mols per second (μmol/s), indicates how many photons in this spectral range fall on the plant each second. Inexpensive PAR meters use sensors that respond over the entire 400-700nm spectrum, and have their own sensitivity curves that require different calibration for sunlight, fluorescent and HID lighting.All these systems are too broadly responsive to measure an LED’s narrow emission spectrum. They make HID light seem brighter by over-measuring yellow-green light, and make LED light seem dimmer by under-measuring red and blue light."
Infelizmente essa informação não está disponivel por aí e teve de ser uns amigos aquariofilistas a fazerem os testes. Não têm as calhas todas mas tem as principais.
https://www.ukaps.org/forum/threads/ada-wasmas-zetlight-twinstar-chihiros-led-par-data-the-power-of-light.43178/