[StanChung]

Sorry to barge in on what seems like a very heated but enlightening 'discussion'.

My take is I prefer substrate feeding after the lengthy read. I even inject liquid fert into the substrate as an experiment and it worked. Overdosing on the ferts have led to mass fauna death in AS/PS setups that are 2 months old. I have two. Cherry shrimps in particular.

I don't see how we can compare to nature that well especially with streams as the water content is constantly changing. Plants IMO will just grab what they need from what they can't get from the substrate.

The science is imperfect because it's human deduction beyond the scope of mathematics. Biology has so many variables.

A very good example is a researcher says that he found XYZ contents in the fish's stomach. Can he conclude that the fish eats XYZ for sustenance?

If you were simplistic you would say yes. If you thought deeper, you would realize that perhaps the fish is really stupid[or really hungry] and just swallowed anything it thought was food?

Sharks for example or even human babies.

I agree wholeheartedly that it depends on your goals.

I would to add that each have to respect each other's views.
Hobbyist's view[like mine] should be taken with a pinch of salt. Ha!

BTW, I don't see algae as a problem anymore. I see it as maintenance or failure on my part to do so.