Reef lights

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Light is the category where people most often overspend on the wrong axis — chasing peak wattage when the thing that actually matters is coverage and even PAR across the footprint. The budget pick, the AI Prime 16HD, exists for one specific job: a single nano or AIO up to roughly a two-foot footprint for softies and LPS, or about 16 inches square at SPS intensity, where one fixture genuinely covers the tank and adding a second would just create overlap. It's a real reef light, not a starter toy. The value tier has two answers. The AI Hydra 32HD is the density pick: it puts enough diodes over a 24-inch footprint that two of them give a standard 36-to-48-inch tank uniform coverage instead of bright spots. The Kessil A360X costs about the same and trades channel control for the best shimmer in the hobby and simple dial controls — the catch is a tighter beam, so plan on overlap over a wide tank. At the premium end, the Radion XR15 Pro (G6) is about spectral control: more independently programmable channels through Mobius, and the headroom to tune a dedicated SPS tank for acropora coloration. The rule that survives all three tiers: buy for coverage first. Two correctly-spaced mid fixtures beat one overpowered one every time, because corals at the edges of a single-fixture tank live in shadow no amount of wattage fixes. Use the PAR and DLI calculators to confirm a fixture actually delivers at your sand bed before you commit — manufacturer coverage claims are optimistic, and mounting height changes everything.

Last reviewed 2026-09-30