The chemical equation of photosynthesis is:
[IMAGE]6CO2 + 6H20 C6 H12 O6 + 6O2
it has been proven many times that plants need light to be able to
photosynthesize , so you can say that without light the plant would
neither photosynthesize or survive.
Prediction: I predict that as the light source (desk lamp) is moved closer to the pondweed (Elodea), the rate of photosynthesis will increase therefore more oxygen will be produced creating more bubbles.
how does light intensity affect the rate of photosynthesis?
These same older generation emitters, controller technology & drivers are the reason I did not recommend LEDs of ANY brand for "higher-end" aquarium applications until 2008 (readers of this VERY constantly evolving article in 2007 would note this too).
However NOW we have many reef/planted aquarium capable LED lights and the only thing that separates most are bells & whistles, cost, efficiency of energy input to output, colors one might desire (albeit not necessarily what the photosynthetic life is more efficient utilizing), water proofing/resistance, and warranty. Even in cost, often the other factors will override an initially low cost of many popular LED fixtures.
Effect of Light on Photosynthesis with an Oxygen Sensor …
Based on email I get, forums I regularly read, & YouTube videos (for DIY LED Aquarium Lights), many seem to make this very INCORRECT assumption about emitters, drivers, PWM, wasted heat energy, etc.
This has resulted in a plethora LED lights flooding the market that are non reef capable, marginally reef/planted capable or very reef/planted capable, BUT often requiring 3-4 times the input wattage for EQUAL efficient PAR!
Basically one is back to the high energy input of a MH, but now in a LED.
It is NOT that many of these LEDs cannot keep photosynthetic life as we know these lights can and do quite well from practical experience, these are simply less efficient due to wasted heat energy, use of more of the less efficient, yellow, amber, green, or binned emitters; QUITE SIMPLE!
How does the level of light affect the rate of photosynthesis
Far worse yet would be the cheaper no name emitters used by manufacturers such as BaiSheng, Epistar, & others sold under a plethora of other names for so-called aquarium use. These use daylight emitters that can vary widely in Kelvin Color output from only 2000K to 6500K and are in reality generally much less efficient for photosynthetic aquarium life use other than just plain light!
Think about why a CFL 10,000K daylight is so much different and more expensive than a common household CFL sold in hardware stores, or the many decorative LED aquarium lights or even those for home or flashlight use. Try using one of these to grow your delicate coral or plants (the answer is they will not without use of many). This is the reason most LED aquarium lights were not adequate for supporting life properly until about 2008-9.
Light Intensity and Photosynthesis by Moesha Grant on …
Implications of these tests:
This controlled test has aquatic implications, as photosynthesis is the same whether it be a terrestrial plant, a freshwater aquatic plant, or symbiotic zooanthellic algae found in corals.
The main difference would be that light energy is quickly absorbed by water, especially red light waves and many modern high-end LED fixtures such as an EcoTech Radion, AI Sol Vega Blue, ZetLight ZT 6600, AAP Fiji Blue, AAP Ocean Blue NP, and AAP Reef White 2000 produce the light energy for deeper aquarium water penetration more comparable to the popular 20k "Radium" Metal Halides.