Aquarium lighting is the second-most-important equipment after filtration. Good lighting drives plant or coral growth, color expression, and fish behavior; bad lighting starves photosynthetic livestock or feeds algae instead. Modern reef and planted-tank LEDs have replaced T5 fluorescent and metal halide as the standard.
Freshwater fish-only: 30-40 PAR is sufficient. Planted low-tech: 30-50 PAR. Planted high-tech: 100-150+ PAR with CO2. Reef softie / LPS: 100-200 PAR. Reef SPS: 200-450 PAR depending on species.
Reef tanks need heavy 420-460nm royal blue plus 380nm violet. Planted tanks need full-spectrum 6500K white with red 660nm peak. Fish-only freshwater can use any reasonable LED spectrum without spectrum-specific concerns.
Nano (under 30 gal): AI Prime 16HD, Reef Brite XHO. Mid (30-65 gal): AI Hydra HD26, Radion XR15. Larger (75+ gal): Radion XR30, multiple Hydra HD52, or T5 hybrid (T5 + LED point source). $200-1500 depending on tank size.
Twinstar 600S/900S, Chihiros WRGB II/Pro, Fluval Plant 3.0, NICREW SkyLED Pro. Look for >100 PAR at substrate for high-tech setups. $100-400 depending on length.
Aquaclear, Fluval Aquasky, Hygger, NICREW. Most $30-100 LEDs work for fish-only or low-light plant setups.
Start at 6 hours of full output, increase to 8-10 hours over 4-6 weeks. Use a 30-minute ramp-up and ramp-down. Longer photoperiods favor algae growth over coral/plant growth in unbalanced systems.
Recommendations on this page cross-checked against the following authoritative references and our internal vendor + breeder database.
Whatever specific topic brought you here, four fundamentals govern long-term aquarium success: water quality, parameter stability, biological filtration, and species-appropriate husbandry. Skip any one and the others struggle to compensate.
Water quality: ammonia + nitrite at zero, nitrate under 30 ppm freshwater + 10 ppm reef. Test weekly with API or Salifert kits. Use our water parameter checker to score your readings against your tank type.
Parameter stability: stable wrong parameters beat fluctuating ideal parameters. Most fish tolerate a wide pH range if it's stable. Sudden swings of 0.4+ pH or 5+°F kill fish faster than chronic suboptimal values. Use temperature controllers (Inkbird) + automated dosing for consistency.
Biological filtration: the bacterial colony on your filter media + rock + substrate is the engine. Never replace all media at once. Use our filter turnover calculator to size correctly.
Species-appropriate husbandry: research adult size, territoriality, diet, and tankmate compatibility before purchase. Use our tank stocking calculator + compatibility guides.
How long does an aquarium take to set up? 4-6 weeks for full cycling + first stocking. Use our cycle ETA calculator + how long does cycling take.
What's the best aquarium for beginners? 20-gallon long. Big enough for parameter stability, small enough for budget + space. See beginner picks.
How often should I do water changes? 25-30% weekly. See water change frequency Q&A + water change calculator.
Why does my fish keep dying? 5 leading causes: uncycled tank, wrong species pairings, no quarantine, undersized tank, neglected water-change schedule. See full diagnosis.
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