Hi @Happi I agree, these pro vs. con discussions tend to go nowhere fast and end up being unnecessarily heated - especially when its unclear what it is exactly that is being debated I don't really know enough from experience to debate "lean" vs. high. What I do know from experience is that lack of consistent fertilization is not working, and providing an abundance of ferts works and without any appreciable side-effects.@MichaelJ
It's one of those debate which is a never ending debate and we are not going to get anywhere. I use to spend lot of time debating and it would go on back and forth without any outcome. So I just let people decide for themselves, if they were to use high light and lean fertilizer and succeeded then that's all the proof you need.
You know a lot more about this than most, but I have seen, again from experience, that high dosing of PO4 eradicating a GSA outbreak in both my tanks. Granted, this was combined with lowering the light intensity, thus lowering the demand for CO2, and upping my WC %... so which factor(s) that had the biggest impact I do not know. Also, battle-tested experts around here consistently make the case about the correlation between PO4 deficiency (and poor CO2) and GSAThis myth is similar to high po4 solving GSA when GSA has nothing to do with this. If true then both myth should hold true when someone is using tropica fertilizer because not only it's lean, but it also adds very little po4.