For clarification, I'm a plant grower - just another guy off the street. Darrel is the biologist.
In any case, since we have all the spores present in the tank it's a race to see which species can conquer the tank. Different algae are triggered, as you mention, by a combination of and variety of conditions. We don't yet have the full story down to the last atom, but at the macroscopic level we have pretty good correlations - as well as pretty good non-correlations which is actually easier to determine by FAR.
We've divide causality by; nutrient deficiency related, CO2 deficiency related, or the combination. Of course it's not just these main categories as there are other factors such as Oxygen deficiency and general chemical instability.
As far as the general categories ;
The "known" CO2 related algae are Hair (and other filamentous types) and BBA. I put the word known in quotes because these are strongly correlated.
The "known" nutrient related is primarily BGA which is typically correlated with poor NO3.
The remaining species are correlated to the combination of poor CO2 and poor nutrient levels, the most prevalent of which is GSA, which is correlated to some combination of poor CO2 and poor PO4. When troubleshooting GSA, one has to analyze the tank keeping in mind that poor CO2 usually will show multiple symptoms - primarily structural faults in the plants, so if no other CO2 related symptoms are evident we then assume the GSA is related to PO4 deficiency. It's easy to add more PO4 and to observe the results. Do the easy thing first. Correcting a CO2 fault is exponentially more difficult.
Diatoms are in a different category and are typically triggered by the chemical instability. There are over 10,000 species. Normally the arise in newly setup tanks and then disappear after a few weeks - but they can be prolonged in the tank if the conditions do not stabilize. Change the water frequently, physically clean the tank and avoid excessive lighting.
Again, we're talking about a planted tank here, not a lake or marine tank or even a fish-only freshwater tank.
It's believed that spores monitor the environment and monitor the plants response to that environment. The mechanism is unclear, to me at least. Deficiency leads to decline in health, which results in degeneration of the plants tissues. The damaged tissues leak their contents into the water column and it is believed that the spores have the ability to detect the contents of the leak and respond by blooming. Healthy plants grow, are tight and are able to resist the attacks. So in these tanks there is a relationship between algae and plants wherein plants are prey and algae are predators.
Few people in The Matrix ever consider this relationship. They just consume regurgitated wives tales and run out to buy delusional test kits and other props such as "phosphoguard" or "nitrazorb", or whatever is fashionable. A tank free of algal blooms is hard work and it's not likely to happen when we fear nutrients or allow a test kit to determine our fate.
Also regarding the article you referenced, I reckon it's another case where the data is taken out of context. I repeat the we have to be careful. The article does not imply that Si is a macronutrient for macrophytes. It is arguing that Si can be taken up by plants when the ambient concentration is high and that they can store high tissue concentration when necessary. Take a look at the first bar chart in Figure 1. It shows a case where in emergent growth, the tissue concentration is about 10,000 ppm Si where the ratio between the tissue concentration and concentration of the dissolved Si in the water is about 2.5. That means the water column Si concentration is about 4000 ppm. Were there diatomic blooms in the water at that concentration level? Unknown.
This demonstrates a win-win in that under the right conditions we can throw the kitchen sink at plants and they will gobble it up. This tells us what we know that plants clean up the environment.
Cheers,
. Or more accurately "people using social media and other internet knowledge sources"
