ITC Reefculture PARwise | Digital PAR & Spectrum Meter for Reef Aquariums

The ITC Reefculture PARwise is a hobbyist-grade PAR meter and spectrometer that ends the guesswork on reef lighting. Drop the cosine-corrected sensor in the tank, plug it into your phone or computer, and read PAR (PPFD), Kelvin (color temperature), LUX, Spectrum, DLI, Peak Wavelength, and Hue — all from a single tool. It is the same data points pros use to dial in coral growth and color, in a sub-$300 package.

Pair the PARwise with our AquaIllumination lighting, browse Water Testing instruments, or shop more Aquarium Equipment.

What the PARwise Measures

• PAR (PPFD) — photosynthetic photon flux density in µMol/m²/S, the key metric for coral & plant growth.
• Kelvin (CCT) — color temperature, so you can match aesthetic targets across fixtures.
• LUX — traditional brightness metric, useful for general-purpose readings.
• Spectrum — full visible spectrum graph; see exactly which wavelengths your fixture is putting out.
• DLI (Daily Light Integral) — cumulative photon delivery over a photoperiod.
• Peak Wavelength & Hue — fine-tune blues, whites, and reds for coral fluorescence and color pop.

Why Choose PARwise

• Fraction of pro-meter cost with measurements typically reserved for $1,500+ lab instruments.
• Underwater & in-air use — a sealed sensor head with user-replaceable cosine corrector.
• Web app, no install — plug in via USB and the Chrome-based PARwise app loads automatically.
• Real spectral data instead of a single-number summary, so you can compare LEDs, T5s, and metal halides apples-to-apples.
• USB-C adapter included for Android phones, tablets, and computers.

Compatibility

The PARwise runs on a web-based app served over USB. It works on Windows, macOS, and Android via Chrome browser. It does not work on iOS or iPadOS — Apple's USB restrictions prevent the connection. If you only have an iPhone or iPad, plan on borrowing an Android device or running it on a laptop.

Specifications

Recommended Pairings

• AI Prime 16 HD (White) — nano-reef LED that benefits from PAR tuning.
• AI Hydra 32 HD (White) — mid-size reef fixture; PARwise helps map shadowing.
• Red Sea ReefLED G2 115 — verify PAR delivery at depth in larger systems.
• Maxspect Jump MJ-L230 — nano LED that pairs well with PAR-mapped settings.
• Water Testing — the rest of our test kit and instrument lineup.

Frequently Asked Questions

What PAR levels should I target?
Rough guidelines: low-light corals (mushrooms, zoas) 50–150 PAR; LPS 150–250; mixed reef 200–300; SPS 300–450+. Measure at the rock or sand surface, not at the water line.

Why does spectrum matter, not just PAR?
Two fixtures can read the same PAR but produce different growth and color. Spectrum tells you whether you have enough blue (corals love 420–470nm) versus broad daylight.

Does it work on freshwater planted tanks?
Yes. PAR and spectrum readings are equally useful for planted-tank aquascapers tuning LED bars to plant species.

Can I leave it in the tank long-term?
It is intended for in-the-moment readings, not permanent deployment. Rinse with fresh water and dry after each saltwater dip.