It is an interesting question, but is there any functional benefit to knowing the answer?
I guess the fact that nobody seems to be able to give a definitive answer is a good enough reason for me to ask the question, especially since I use algae scrubbers.
There could be differences between the two that could be important to consider when utilising algae as a filtering mechanism?
Not so much what they take out of the water, although how fast they do it is important, & speed of growth is a determining factor , but what they put, or potentially put into the water.
Example; I've read comments from people that suggest macro algae literally produce toxic substances & this is why algae scrubbers (& I take it refugiums also) should not be used in an aquaria. If true, what type of alge?
Another example; some people swear that a continuous photo-period, rather than a day night cycle, improved the growth on their screens. In a discussion with another hobbiest, I quoted your article '
Photosynthesis and the Reef Aquarium' Continuous Light vs. Light/Dark Cycles, &, Rost, Bjoern; Riebesell, Ulf; Sueltemeyer, Dieter. Besides pointing out that microalgaes were used in their anaylsis (this hobbiest believes that scrubber algae is macro & results could differ for this reason) , he also, quite rightly, suggested that growing algae in a test tube does not mimmic algae growing in agitated water (flashing) like in a scrubber. It was suggested that a day/night cycle is probably no more benificial in comparison to this flashing effect (rapid on/off cycle).
I don't know?
The only source of knowledge is experience. Albert Einstein
