Guide
Lighting: what are the different types?
From old-school incandescent to modern LED — a clear guide to aquarium lighting so you can choose what fits your tank and your goals.
Why lighting type matters
Light affects how your tank looks, how well plants grow, and how much algae you get. Fish-only tanks need enough light to see the fish and keep a day/night rhythm; planted tanks need the right spectrum and intensity for photosynthesis. Too much or the wrong type can fuel algae; too little and plants suffer. Understanding the options helps you match the light to the job.
LED (light-emitting diode)
What it is: The standard for most new setups. LEDs are small, efficient, long-lived, and can be tuned for colour (spectrum) and intensity. Many units offer adjustable brightness, sunrise/sunset, or programmable schedules. Pros: Low heat, low power draw, long life, minimal bulb replacement. Cons: Good plant or reef LEDs can be pricey upfront. Best for: Almost everything — fish-only, planted, and reef. Choose “full spectrum” or “plant” LEDs for growing plants; basic white LEDs are fine for fish-only.
Fluorescent (T8, T12)
What it is: Tube lights that were the norm for decades. T8 and T12 refer to tube diameter. Often sold as “daylight” or “plant” tubes. Pros: Inexpensive, even spread, familiar. Cons: Less efficient than LED; bulbs need replacing every 6–12 months; limited intensity for demanding plants. Best for: Fish-only or low-light planted tanks; budget setups.
T5 and T5 HO (high output)
What it is: Thinner, brighter fluorescent tubes. T5 HO puts out more light per tube than T8. Pros: Good for medium-light plants; multiple tubes let you mix spectrum (e.g. one daylight, one plant). Cons: Bulbs need replacing periodically; more heat and power than LED. Best for: Planted tanks where you want strong growth without going full LED; some reef keepers still use T5.
Incandescent
What it is: Old-style screw-in bulbs. Reality: Inefficient, hot, poor spectrum for plants, and mostly obsolete for aquariums. Avoid for new setups.
Spectrum and photoperiod
Plants use red and blue light most; many LEDs are sold as “full spectrum” or “plant” to include these. For algae control, keep the photoperiod to 6–8 hours and avoid direct sunlight. Use a timer so the schedule is consistent — your fish and plants will thank you. If you track tank setup and maintenance in an app like App-aquatic, note your light type and schedule so you can spot patterns (e.g. algae after increasing hours).
Quick takeaways
- LED: efficient, long-lived, adjustable; the default choice for most tanks.
- Fluorescent (T8/T12): cheap and even; good for fish-only or low-light plants.
- T5 / T5 HO: brighter tubes; good for planted tanks without going high-end LED.
- Match spectrum and intensity to your goal (fish-only vs plants); keep photoperiod to 6–8 hours to limit algae.