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Best Aquarium Light for a Planted Tank

3 min read · Updated Jun 2026

The right light grows lush plants; the wrong one grows algae. Here is how to choose a planted-tank light, and the picks we recommend at each budget — from nano tanks to programmable mid-tech setups.

In this guide

Lighting is where a lot of planted tanks quietly go wrong. Too little and plants melt; too much without CO2 and the tank turns into an algae farm. The good news is you do not need an expensive fixture to grow a healthy low-tech tank — you need the right spectrum, the right intensity for your plants, and a timer to keep it consistent.

What makes a good planted tank light

Four things matter more than brand:

  • Full spectrum. Plants use red (around 660 nm) and blue (around 450 nm) light most, so look for a full-spectrum LED rather than a plain white hood light.
  • Intensity matched to your plants. Low-tech plants want modest light; demanding carpets and red stems want more (and CO2 to match).
  • A built-in timer. Consistency beats intensity. A timer that runs the same photoperiod every day prevents the swings that trigger algae.
  • The right length. Buy a fixture rated for your tank's length, ideally with adjustable mounting brackets.

Match the light to your plant ambitions

Before you buy, decide what kind of tank you want:

  • Low-tech (no CO2): Anubias, Java fern, mosses, and crypts thrive under modest light. Keep intensity moderate and the photoperiod short.
  • Medium to high-tech (with CO2): Carpets, stem plants, and red plants need stronger light — but only alongside CO2 injection and regular fertilizing. More light without CO2 is the single most common cause of an algae outbreak.

Our picks

Best for nano tanks — NICREW Clip-On Nano

For tanks up to about 20 gallons, a compact clip-on light delivers plenty of growth without dominating a small setup.

NICREW Clip-On Nano Aquarium Light

Clean, bright light for nano tanks that keeps low-light plants and moss happy.

Best value all-rounder — NICREW ClassicLED Plus

A full-spectrum LED with a built-in timer that grows most low-to-medium-light plants, at a price that is hard to argue with. For the majority of low-tech planted tanks, this is all you need.

NICREW ClassicLED Plus Planted Light

Great value full-spectrum LED that grows most easy to medium plants.

Step up: programmable 24/7 — Hygger Advanced

If you want a sunrise-to-sunset cycle, more brightness for demanding plants, and fine control over color and intensity, a programmable fixture is the upgrade. It costs more, but earns it on a medium-tech tank.

Hygger Advanced Full Spectrum Planted Light

Higher PAR with a built-in 24/7 timer — drives lush growth on planted tanks.

How to choose the right size

Measure your tank's length and buy a fixture rated to span it. Most LED bars list a supported length range and include extendable brackets that rest on the rim. A light that is too short leaves dark corners where plants struggle.

Common mistakes

  • Running the light 10+ hours a day, which grows algae rather than plants
  • Adding a high-output light to a tank with no CO2, then fighting algae
  • Buying a fixture too short for the tank, leaving dim ends
  • Skipping the timer and lighting the tank inconsistently

Low-tech vs high-tech in practice

If you are new, start low-tech: easy plants, a value LED on a 6 to 7 hour timer, and a liquid all-in-one fertilizer. Get that stable first. Stepping up to high light, CO2, and demanding plants is a deliberate next project — not the default.

Spec your planted tank

Use our Tank Builder to get a complete planted setup — light, substrate, filter, and the gear sized to your tank.

Build my tank kit

Once you have matched the light to your plants and put it on a timer, lighting becomes the easy part — and the comparison most beginners actually face is NICREW versus Hygger, which we break down next.

Frequently asked questions

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