Re: My new nameless scape!
The-Green-Machine said:
For the record, the Morena or for that matter any similar product acts as a subtractive colour filtering agent.
When added the water column, which turns a golden yellow acts as a yellow filter removing much of the blue and uv from the colour spectrum and thus depriveing algae of its preferred light spectrum.
It has been observed in certain shallow Amazon streams that run clear, algae is extremely prevalent, conversely, similar streams which are stained with tannins seem to be algae free.
The proof of the pudding however is in the eating and all I can say is that it works for me and seems to have done so for you.
Of course gravy browning would probably do the same job but then I dont think we would really want that in our tanks lol
Anyway, once again great tank and looking forward to seeing you soon,
Take care and happy planting,
Jim ann Mark,
TGM.
Hi,
Many of the theories regarding algae light preference have been based on the studies done in oceanography. The sea is blue because water absorbs the higher wavelengths. Marine algae take advantage of this by producing pigments to absorb blue light and thus can be found at deeper levels relative to corals for example.
In fresh water the situation is a bit different. Higher plants share exactly the same photosynthetic mechanisms as algae, specifically, the distribution and content profile of special pigment cells. I have no doubt that the tea stained and black water tributaries of the Amazon river basin would tend to have a lower incidence of algae, however, I'm sure that further investigation will reveal that these tributaries also will tend to have a much lower population of plants as well.
Both plants and algae have a distribution of various pigment types, not just chlorophyll, that enable them to take advantage of the spectral quality of the light in their environment. In natural systems the spectral quality of the light varies minute by minute, but there is a general trend of red/orange/yellow light early in the morning and blue light near midday. As a result, both algae and plants contain an arsenal of non-chlorophyll pigment types specifically suited to the absorption of certain wavelengths other than blue. These pigment cells are referred to as "Accessory Pigments" and among many others, include the following general types of pigments:
Carotenoids, which are normally fat soluble. these are responsible for reds, yellows and orange colors of many fruits and vegetables
Xanthophylls, which are water soluble, a carotene derivative, typically yellow/orange.
Flavonoids, which are yellow and red/blue and are often found in flowers.
Additionally, algae and plants, depending on their specie, use specific pigments to protect (by fluorescent reflectance) against damage due to an overabundance of light energy in the visible and non-visible spectrum or to gain a specific advantage in certain spectral environments. A few example are as follows:
Phycocyanins absorbs orange and red light, particularly near 620 nm, and emits fluorescence at about 650 nm.
Allophycocyanin absorbs and emits red light (650 and 660 nm), and is readily found in Cyanobacteria (AKA BGA).
Phycoerythrin is a red protein which absorbs energy in the 480-565 nm range.
An additional point often ignored is that as a result of the spectral changes which occur on a daily basis as mentioned above, it turns out that plants and algae simply use the daily spectral profile to regulate their metabolism. Experiments were performed by irradiating algae using red light. It was discovered that these red wavelengths stimulate carbon fixation in the algae, in effect making them more efficient at using CO2 and better able to produce glucose and sucrose.
When blue light was added, there was an immediate shift in metabolism wherein glucose and sucrose production ceased and instead, the fixed carbon was used in the synthesis of organic acids, amino acids, and proteins.
The vast inventory of non-chlorophyll pigments produced by plants and algae allow a much greater range over the spectrum than using Chlorophyll alone. Plants can and do change the concentrations and type of these pigments to suit their environment. Algae essentially do exactly the same thing either at the single or colonial cell level. Thus, changing the spectral output in the tank does not result in any advantage over algae. In fact these experiments, as well as others demonstrate the incredible adaptability of plants and algae in regards to spectral efficiency. They prove unequivocally the there is no such thing as a "plant specific" light bulb or an "algae-unfavorable" light spectrum. Plants and algae alike simply adapt to and assimilate whatever spectral environment is available.
Therefore the amount of peat extract or Morena that would be required to have any significant effect on the algae in this or any tank would be so high as to affect the photosynthetic and metabolic processes of the plants themselves. Algae cannot be outwitted in any way, shape or form. The best stratagem in plant husbandry therefore is to focus on the the needs of the plant first and in that way healthy plants will deter algal blooms. It is for this reason that the use of Excel/Easycarbo will return more dividends than any peat extract or black water tonic could ever dare to dream of. If this product is being added for the fauna, and if it has proven it's worth in this regard then, yes fine, but the hypothesis that it is an algal deterrent due to spectral suppression cannot be shown. Proof of pudding is also not valid as there are many variables in biochemistry that can result in optical illusions, coincidences and false correlations. As empirical evidence, the spectral profile of my tank includes high levels of blue as I have several blue bulbs, and yet, I have no algae. Therefore the spectral mechanism of this product cannot be correlated to algal decline unless sufficient quantities are added to lower the spectral energy level in the tank to a level below the Light Compensation Point (LCP) of the algae.
Cheers,