How many LED fixtures do I need for a 4-foot reef tank?

For a 48-inch tank plan on two fixtures spaced evenly — for example two AI Hydra 32HDs or two Radion XR15s. A single high-output fixture will produce hot spots in the center and dead, low-PAR zones at the ends where corals will struggle.

Is a protein skimmer necessary on a nano reef?

Not strictly. Many nano reefers run skimmerless with frequent water changes and good macroalgae or a refugium. But on anything over ~30 gallons with a moderate fish load, a skimmer makes nutrient control far easier and more consistent.

Can I use a powerhead instead of a wave maker to save money?

Yes, for softie, LPS, and fish-only tanks a fixed-flow powerhead is completely adequate and much cheaper. SPS-dominant tanks benefit from a controllable wave maker's variable, pulsing flow, which improves nutrient delivery and prevents detritus buildup.

By the ReefLab Editorial Team · 4 min read

Best Reef Tank LED Light Comparison — An Honest Buyer's Guide

Most reef gear buyer's guides are just affiliate link farms. This one is written from the perspective of someone who has actually killed coral by picking the wrong light. Below is a real comparison of the LEDs that matter in 2024, plus honest answers on the three other questions reefers ask constantly: skimmers for a 100-gallon system, all-in-one nano tanks, and whether you need a wave maker or a powerhead.

Reef tank LED light comparison: what actually matters

PAR (photosynthetically active radiation) at your coral's depth is the only spec that keeps SPS alive. A light that pushes 250+ PAR at 18 inches under water will grow Acropora; one that reads 90 PAR will bleach it slowly. Spectrum matters for color and coloration, but PAR is the survival number. Coverage per fixture is the second thing people underestimate — most brands overstate their spread by 4-6 inches.

The honest spec comparison

Light	Price band	Best for	Key spec (PAR/coverage)	Trade-off
AI Prime 16HD	$220	Nano/24" cubes	~250 PAR at 12", 24"x24" coverage	Small footprint, weak shadowing on wide tanks
Kessil A360X	$429	Point-source shimmer lovers	~300 PAR at 18", 24"x24"	Fewer channels; needs Spectral Controller for full control
AI Hydra 32HD	$430	Mixed reef 24-36"	~350 PAR at 18", 24"x24"+	Fans can whine after 2 years
Radion XR15 G6 Pro	$400	SPS dominant nanos	~330 PAR at 18"	Ecotech ecosystem lock-in
Radion XR30 G6	$800	Large SPS displays 30"+	~450 PAR at 20"	Expensive; overkill for softies
Nicrew HyperReef	$130	Budget softie/LPS tanks	~180 PAR at 12"	Weak spectrum control, no app scheduling depth

Rule of thumb: one AI Hydra 32HD or Radion XR15 per 24 inches of tank length covers a mixed reef. For a 4-foot SPS tank, budget two XR15s or two Hydra 32s — a single fixture will leave dead spots at the ends.

Best protein skimmer for a 100 gallon tank

The number-one skimmer mistake is buying to your display volume instead of your total system water and bioload. A 100-gallon display with a sump is really ~120 gallons of water, and if it's a fish-heavy tank you want a skimmer rated for roughly 1.5-2x your actual volume.

Reef Octopus Regal 150INT (~$400): rated to 210 gallons, handles a heavily stocked 100g with room to spare. My pick for most builds.
Nyos Quantum 160 (~$470): quiet, dry foam, excellent for SPS tanks where you want aggressive export.
Bubble Magus Curve 7 (~$180): budget in-sump option, honest rating around 130 gallons, good for a moderately stocked system.

Skip anything rated exactly at 100 gallons — you'll never get consistent skimmate as your stock grows.

Best all in one nano reef tank

All-in-one (AIO) tanks hide the filtration in a rear chamber, which is perfect if you want a clean look without a stand full of plumbing. They differ mainly in build quality, glass clarity, and how much space the rear chamber steals.

Top picks by size

Waterbox Cube 20 — best overall AIO. Low-iron glass, generous rear chamber that fits a real skimmer and heater. Pair with an AI Prime 16HD.
Innovative Marine NUVO Fusion 20 — great value, includes a return pump and media basket, easy to source parts.
Red Sea MAX NANO (20g) — most complete out-of-box package with light and pump included; premium price but plug-and-play.

Avoid tiny 5-10 gallon AIOs for beginners — the smaller the water volume, the faster parameters swing, and one dead snail can crash the whole system overnight.

Aquarium wave maker vs powerhead — which do you need?

These terms get used interchangeably, but they aren't the same thing. A powerhead pushes water in a fixed, constant flow. A wave maker is a controllable pump (or a controller that drives one) that pulses, ramps, and randomizes flow to mimic ocean surge.

When a plain powerhead is fine

Softie and LPS tanks, or fish-only setups, do great with a fixed-flow powerhead like a Sicce Voyager. Cheap, reliable, and enough turnover.

When you want a controllable wave maker

SPS corals thrive on variable, chaotic flow that prevents detritus from settling and delivers nutrients evenly. A gyre-style pump like the Maxspect Gyre XF350 or an Ecotech MP40 in reef-crest mode makes a visible difference in polyp extension and growth. Expect to pay $150-300 versus $30-60 for a basic powerhead.

Putting it together: a sample 100-gallon mixed reef

Lighting: 2x AI Hydra 32HD (covers 48" of length)
Skimmer: Reef Octopus Regal 150INT
Flow: 2x Ecotech MP40 in alternating gyre mode
Total lighting + flow + skimmer budget: roughly $1,700

The takeaway

Buy your light for PAR at depth and honest coverage, not marketing wattage. Size your skimmer above your real system volume. Choose an AIO nano with enough water and rear-chamber space to be forgiving. And only pay for a wave maker if you're keeping SPS — softie keepers can save $200 with a simple powerhead. Match the gear to the corals you actually want, and the tank runs itself.