The Light-Dependent Reactions of Photosynthesis
Introducing: Photosynthesis (The Light Reactions)
It is also noteworthy that in acidic environments phosphate ions react with Iron and make iron less soluble and thus less available. Therefore if one require more iron, slightly alkaline values are more desirable.
What Kind of Reaction Is Photosynthesis? | Sciencing
*GH (general hardness): 100 ppm or sometimes higher; this is more important than many realize for planted aquariums.
During photosynthesis, a rise in pH can occur in water with low alkalinity (20 to 50 mg/L) or in water with moderate to high bicarbonate alkalinity (75 to 200 mg/L) that has less than 25 mg/L hardness.
Photosynthesis (Light Reactions) - YouTube
The watts-per-gallon" formula was based on the older T8 & T12 fluorescent lights, many of which were not of optimum PAR/Kelvin and especially PUR, and are severely lacking in the area of lumens per watt. Besides that, "useful light energy" (aka PUR) is something that is often overlooked and is an area where the new generations of LED lights that emit "natural daylight" spectrums cannot be beat.
That being said, along with Metal Halide, the new generation SHO and T5s are also relatively strong in this area. Lumen focus and restrike is an area in which the LED and metal halides reign supreme with almost all light energy directed where the light needs to be: in your aquarium.
Light Reaction of Photosynthesis Essay - 616 Words
The beginning aquarist is likely to think that if there's enough light to see then it's enough for plants to grow.
However, that's not true. If you want to grow healthy plants, and not just algae, you need enough light for them to use for photosynthesis and create energy.
It used to be that people advised 3-4 watts per gallon as a VERY basic principle. But, due to modern lighting technology this is now considered an outdated notion (with PAR now more the norm).