2Hr Aquarist Commentary: Wavepoint has several choices (the Amazon picture featured here may look yellow but the specifications would be 6700K). The Giesemann Tropic bulb is good too. The key difference between using these bulbs (vis a vis everyday home-lighting daylight bulbs) is the better spectrum distribution in these horticultural bulbs. Many household bulbs have large spikes in the green spectrum (which human eyes are more sensitive to) while we would prefer spikes in red and blue for plant growth and which also give better colour rendition.
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