http://www.prirodni-akvarium.cz/en/index.php?id=en_algaeTOC
I'm inclined to agree with the hypothesis. I used as different method in the past that I think is highly effective for the loading rates.
I added progressively more and more fish slowly, to a high light well run aquarium. Until, you guessed it, algae.
The patterns I saw: Green water was 1st, then BBA, then Staghorn.
Same thing when I uprooted a lot of jobes sticks in the sediment.
This led me to hypothesize that NH4 was the cause. This was false however as we can dose NH4 at relative low levels, ADA As has a fair amount as do soils etc and not get algae issues.
If the CO2 is slightly poor/not optimal, and you add NH4, then you can get Green water, but the others? Not so much.
A standardized method to to progressively and slowly increase the loading rates in a well run panted tank is the key to the methods.
I think adding progressively small sized fish can accomplish this easily and relatively cheaply, eg, you could use bait minnows or guppies etc. You need to feed them so the amount of food needs to be considered also and type.
Measuring COD is not easy, you need a heating block or a water bath. So it cost more than many other methods. But not as bad as a lot of things.
I've been meaning to do this for sometime and I think Jeffery got me going again when I'd put it on the back burner.
Doing mesocosm and bench scale test, then seeing how well that data correlates to existing field data would be a nice support for looking at getting a grant to do a manipulative research project in the field.