Fish Tank Light Complete Guide: LED, Spectrum, Duration
Lighting is the one piece of aquarium equipment where the right choice transforms a tank into a display and the wrong choice fuels a six-month algae war. This fish tank light complete guide covers LED technology, spectrum matching to livestock goals, photoperiod scheduling, and the brand landscape in Singapore — Chihiros, Twinstar, Fluval Plant, Week Aqua and ADA — with SGD pricing from C328 Clementi, Green Chapter and Polyart. At Gensou Aquascaping, 5 Everton Park, lighting choices are the single most frequent consultation we field because the market churns new products every quarter.
Why LED Replaced Everything
Fluorescent T5 and T8 tubes are effectively obsolete for freshwater setups — LED fixtures draw one-third the wattage for the same photon output, last 30,000-50,000 hours versus 6,000-10,000 for tubes, and support programmable spectrum and dimming that tube ballasts cannot. Singapore’s electricity at SGD 0.32/kWh makes the efficiency gap a meaningful ongoing saving; over five years, a 40 W LED fixture saves SGD 250+ versus a 120 W T5 setup.
Spectrum Basics: Kelvin and PAR
Colour temperature in Kelvin describes how warm or cool the light appears — 6500K matches noon daylight, 8000K is cooler and reads blue-white, 10000K suits marine and bluish planted looks. PAR (photosynthetically active radiation) measures usable light for plant and coral growth in μmol/m²/s — a more useful metric than lumens for aquarium purposes. Low-light plants need 30-50 PAR at substrate; high-light carpeting plants want 80-150 PAR.
Chihiros WRGB II and Vivid II
Chihiros’s WRGB II series (SGD 165-320) at 30-120 cm lengths is the dominant mid-range planted fixture in Singapore. App-controlled via Bluetooth, spectrum adjustable across white, red, green and blue channels, PAR sufficient for medium-light stem and carpeting plants. The Vivid II at SGD 240-380 steps up to higher output for demanding Dutch-style scapes. Both stock at Green Chapter, Polyart and Aquarium Kingdom.
Twinstar S/E Series
Twinstar’s S-line (SGD 185-350) and the premium E-line (SGD 350-680) are the Korean-made fixtures favoured for IAPLC-level aquascapes. PAR output per watt is class-leading, spectrum richness brings out red plants vividly, and the slim profile suits rimless tanks. Expensive but unmatched for high-end planted displays. Available at Green Chapter and via specialist pre-order.
Week Aqua P and L Series
Week Aqua’s P200 and L600 (SGD 220-420) bridge the mid and premium segments with app-controlled RGB+UV channels and thoughtful mount hardware. Growing popular in Singapore over 2025-2026 as a Twinstar alternative at lower cost. Spectrum out-of-box is slightly blue-heavy — adjust the red channel up 15-20% for typical red-heavy planted scapes.
Fluval Plant 3.0 and Sea Marine 3.0
Fluval’s Plant 3.0 Bluetooth at SGD 185-295 for 60-120 cm lengths is a reliable entry to mid-level option available at mainstream retailers. App-based schedule and dimming, reasonable PAR for low-to-medium light scapes. The Sea Marine 3.0 variant targets reef tanks with stronger blue and actinic channels at similar pricing.
Budget Tier: Chihiros C2 RGB
Chihiros C2 RGB (SGD 105-145) at 30-60 cm covers nano planted scapes affordably. Fixed-schedule RGB without Bluetooth app, but PAR at 30 cm depth is adequate for Monte Carlo, Staurogyne, and most stem plants in low-medium setups. Good first fixture before investing in WRGB II when your scape ambitions grow.
Photoperiod Duration
Standard photoperiod for planted tanks is 6-8 hours daily at full intensity with 30-minute sunrise and sunset ramps. Less than 6 hours limits plant growth; more than 9 hours feeds algae without proportionate plant benefit. Split photoperiods (4 hours morning + 4 hours evening with a 2-3 hour midday siesta) can reduce algae in newly set up tanks, but the evidence is mixed and most mature tanks do fine with a single block.
Intensity and Dimming Strategy
Start new tanks at 40-50% intensity for the first six weeks while plants acclimatise and biofilms establish. Bump to 70% for weeks 7-12, then 80-100% for mature scapes. Jumping straight to 100% on day one guarantees diatom and green-dust algae blooms. App-controlled fixtures make this ramp trivial; non-dimming fixtures need physical height adjustment or neutral-density screens.
Photoperiod Electricity Cost
A 40 W LED fixture at 8 hours daily draws 9.6 kWh monthly, costing SGD 3.07. A 60 W fixture runs SGD 4.61. A 100 W high-output fixture runs SGD 7.68. Lighting costs are trivial on the monthly utility bill — there is no financial reason to shortchange intensity on a planted tank once you have committed to plants in the first place.
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5 Everton Park #01-34B, Singapore 080005 · Open daily 11am – 8pm
