I was a fan of blue lighting.
However, I recently challenged my beliefs. I did some reading from people I respect in this hobby.
I’ll give some quotes on what changed my opinion.
I’ve always felt standard reef T5 bulbs were
lacking in the red (660nm) for photosynthetic shallow water animals. I also currently believe the lack for yellow/amber light cause corals to lose their chromoprotein pigments overtime, like the “battle coral” phenomenon.
I did some searching on 6500K full spectrum T5, and I’ve settled on the Giessmann Super Flora bulbs because I really that spectrum, specifically because of that red peak at 660nm. The high amber/yellow also helps a lot.
Edit: I’m actually going to try the Tropics because too much red might cause bleaching in corals. The tropics is what most people use for 6500K, including Adam from Battlecorals in his T5 tank.
I’m going to mix in a few in my fixtures to see if there are any noticeable changes in my aquarium.
However, I recently challenged my beliefs. I did some reading from people I respect in this hobby.
I’ll give some quotes on what changed my opinion.
Although not discussed much greenish-yellow/yellow light seems to induce non-fluorescent red coloration in those stony corals capable of producing this pigment.
In short, while PAR meters' estimations of PPFD are useful, it ignores the positive impacts of UV-A and far-red/infrared radiation.
Be careful with graphs like this. Looking at this graph leads one to believe spectrum based on these curves shown is somehow best. I'm not saying success can't be achieved making decisions on this info, but there's a lot more to the story. Look at the line showing absorption for carotenes - this includes beta-carotene that can actually act as a photo-protectant (beta-carotene is found in carrots (! -carrot-tene) and makes them appear orange because they absorb violet/blue light.) Hence, they compete with chlorophylls for blue light. The same can be said for xanthophylls - oxygenated carotenes - they absorb blue light as well. In short, merely looking at the graph leads one to think blue light is most strongly used in photosynthesis. Based on PAM fluorometry experiments' results, red light is most efficient while graphs like this suggest otherwise.
It is no accident that fluorescent pigments that absorb UV-A, blue and violet light and hence subtract from light available to photosynthesis if blue light is of high intensity (relative to what is seen in nature.) Coral fluorescence is another tool in the arsenal of zooxanthellae photoprotection.
I’ve always felt standard reef T5 bulbs were
lacking in the red (660nm) for photosynthetic shallow water animals. I also currently believe the lack for yellow/amber light cause corals to lose their chromoprotein pigments overtime, like the “battle coral” phenomenon.
If anybody thinks that any of this is a joke, search around for frags coming from really good vendors, like BattleCorals, where they are grown and raised with a lot of full-spectrum lighting. They look really good at first and then the colors fade when they are kept under heavy blues only and they lose some color over time. This is a common thing. Easy to sell these folks on more daylight trips to the gym, good diet and some sunscreen or other skin care.
Edit: I’m actually going to try the Tropics because too much red might cause bleaching in corals. The tropics is what most people use for 6500K, including Adam from Battlecorals in his T5 tank.
I’m going to mix in a few in my fixtures to see if there are any noticeable changes in my aquarium.
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