Fine Tuning Light Spectrum

September 04, 2020 1 min read

Fine Tuning Light Spectrum

How can you boost plant colours further?
If you use T5s, this involves fine-tuning the bulb array to have a mix of colours. For LEDs, it is looking out for stronger red/ blue diodes.


When using LEDs, choose a diode mix of more reds ( 50%+). An example of the effect of red heavy LEDs on an ADA 120p tank using custom built BML LEDs.

Dennis Wong LED choice

The diode configuration ratio is as of below. White LED diodes already contain significant amounts of blue, so we opted instead to add orange/yellow tones to round out the spectrum.

BML LED Diodes

BML no longer makes planted aquarium specific fixtures. However, one can experiment with similar ratios in custom builds. For the Twinstar LED series, the E series come with heavier weighting in blue, while the S series is red heavy.


When using T5s, here are examples of different combinations and the resultant impact on the tank. This is Joe Harvey's combination using 6 tube array below; read his full journal here

Joe Harvey's T5 array

Joe Harvey T5 array

Joe Harvey T5 tank

2Hr Aquarist T5 Array

This is the combination we use on our farm tank:

Dennis Wong T5 array

Dennis Wong Farm Tank 1 T5

Dennis Wong Farm Tank 2 T5

Tom Barr's T5 Array

Tom barr's 120 gallon aquarium tank and 8 bulb combination. Read the full journal here.

1 Giesemann Aquaflora
2 Zoomed Flora
3 Sunwave Wavepoint
4 Red Wave Wavepoint
5 URI Red Sun
6 Sunwave Wavepoint
7 Zoomed Flora
8 Giesemann Aquaflora

Tom Barr T5

Daniel Constantin Deacu's T5 array

Daniel Constantin Deacu T5 array

Daniel Constantin Deacu Tank T5

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