AI Prime 16HD is the dominant nano-reef LED in 2026 - well-tuned spectrum, programmable through MyAI, hits PAR 200-300 over a 20x20 footprint at 8 inches off the water. Kessil A360X is the next-best alternative for a more shimmer-heavy aesthetic. Reefi Lumix Slim is the budget choice. Skip multi-fixture setups under 30 gallons.
Nano reef tanks (under 30 gallons) have an LED-fixture market all to themselves because the form factors are smaller and the PAR requirements are tighter. The wrong fixture either fails to grow coral or burns it.
The Prime 16HD covers a 20x20-inch nano tank from a single fixture mounted 8-12 inches off the water. PAR is 200-300 at the substrate when set to a balanced reef spectrum (heavy royal blue with violet and a touch of white). MyAI app on phone or desktop is the cleanest control software in the market for nano-tank programming. Runs cool, lasts 10+ years.
If you want the dappled "underwater" look that reef photographers chase, the Kessil A360X delivers it better than any panel LED. Two-channel control (color and intensity) is simpler than the AI multi-channel approach but produces less precise spectral tuning. PAR is comparable to the Prime 16HD; the trade-off is aesthetic.
Reefi Lumix runs 30-40% cheaper than the Prime 16HD with comparable PAR and a similar-quality app. Newer brand, less of a resale market, but the coral-growing performance is documented and reliable.