Ok, so, my question is this: have you noticed any positive or negative difference in dosing Burr's mix compared to CSM with Aquasoil? Just curious, because in Burr's tank the mix is doing wonders, and in my tank seems to have similar effects (I have increased dosing in the past week and I have noticed a big improvement in all plants, AR included!)... in Burr's case and maybe in my case as well, it really looks like EDTA Fe was the main cause of problems.
No, I have not noticed significant difference between CSM versus Burr mixes. But that's the short answer.
Rambling answers are more my thing (this is, after all, page 88). Rough history of traces in the Dutch tank: I've been dosing low traces for a year or two now. So when I transitioned to the first Burr mix, it was still super low doses. After that, I used trace element blends based on Marschner's textbook, which was even lower in concentration than anything I'd tried. The Marschner ratios may have been right, but the quantity of minerals, especially iron, was grossly insufficient. So I began dosing 2X Marschner (better) and then 3X Marschner (much better.) I've only used Burr's current mix for a week. So, too soon to tell.
I no longer have AR Mini in the tank. It would have told me if/when I began adding too much traces. So, I don't have that indicator any more.
My macros have always been somewhat high. It's the traces I monkey around with. Lowering it did not fix Rotala/Ammannia tip stunting or any of the usual problems I have with the Dutch. So I've begun going up on trace dosing, for entirely different reasons than Burr.
The issues Burr has with CSM+B is that the EDTA breaks down in his tank's pH and that the blends may not be properly mixed since CSM is designed for large-scale use. My pH is low, so I don't have the issue of EDTA breaking down. Also, I do 65% water changes every week, so no EDTA accumulation to cause issues.
I am not sold on EDTA as the bogeyman. Yes, at higher pH, the chelation breaks down and that can cause secondary issues. But EDTA by itself, at doses we toss into tanks, may not be even close to being harmful. One way to find out. We could always add this: https://www.amazon.com/Pure-Disodium-Powder-Ounces-grams/dp/B074CTMWB8
I don't think I'll get any volunteers.
I'm gradually increasing traces because lowering it did not fix what I thought it might.
If noobs are reading this, they'll get the wrong message. Beginners get the biggest bang for the buck from focusing on stability and richness of CO2, followed by reducing light and a daily commitment to wet-elbow maintenance. Light and macros are easy. So is GH/KH. Tinkering with trace element ratios are only worth your time AFTER you've optimized all other aspects of your tank. One look at Burr's tanks these days tells you that he's optimized everything. So it is only fair that he plays with trace blends, with good dividends too.