I'd be really surprised if the exact calcium:magnesium ratio was relevant.
Yeah I'm of the same opinion, doesn't hurt to ruminate on the minutia in a paper on Borneos forests though. I am leaning toward the 10:1 ratio in the interstitial soil as a byproduct of Magnesium having a 10x solubility ratio than Calcium and that weathered limestone (or evaporative conditions at water margins) forms part of the sample bumping the ratio up, the soil itself will be the broken remains of other riparian/epiphytic plants that collects in the cracks and crevices forming a matrix over/amongst the limestone, given all things equal that tissue would have Ca:Mg to give up in a ratio of 3:1.
It would be interesting if in the future you decide to bring the Mg down what results (if any) you may have.
Before I even start messing with ratios again I want to try in another tank to bring the water conductivity right down to the levels that Buce see in the wild in pristine Forrest over limestone to see what happens. The conductivity is 40 micro Siemens, taken from a water sample on the Kelian River above the Kelian Gold deposit (
this is the paper the data is from), Alkalinity as CaCO₃ 13.47ppm, SO4 5ppm, Fe 0.06ppm, Mn 0.01ppm, Zn 0.01ppm, Ni <0.02ppm, Cu 0.00ppm (likely present in ppb). No idea for B, Mo and other trace elements, they will be there though in the ppb/ppt range.
I can understand how you quantify what’s going in, but what is being used to measure the consumption.
In my situation mainly through observation of negative plant response (Bucephalandra) to something bottoming out or accumulating when extending water change periods. I have tested for how Iron (mix of Gluconated Iron and DTPA) behaves in my tank when dosed so I can dose daily along with the other traces (unchelated) to an amount where Iron shouldn't accumulate to any great significance between water changes. As I front load my Macro dose at water change (ideally weekly) I can extend the period between the water changes allowing me to see negative responses in the plant, which is that new leaf growth slowed and it took three weeks for first leaf to curl in a Blue Theia, an upward rolling curl to a whole leaf, a Cherry Red new grown leaf curled tightly downward around the perimeter, Motleyana Wavy Green curls its leaves anyway so tough to say what's going on with that, it straight out melts on me when its really unhappy, Theia does that too to a lesser extent. It was near on 4 weeks for the first sign of leaf senescence in the Blue Theia. Week two saw me add back MgNo3 and KH₂PO₄ at the amount I would normally put in at water change, on titration testing PO₄ had completely bottomed out, Nitrate was still present (perceived accuracy/inaccuracy of the consumer titration tests considered, especially the nitrate), I would have dosed it again at the end of week 4 but I chickened out and performed a 75%ish water change (because I've seen seen the horror of Bucemaggedon too many times to become bored of it, not as scary as Anubiageddon though, that movie had killer worms in it!). I am as yet undecided if the deficiencies leading to melt are due to an element bottoming out or something else detrimentally accumulating (metal toxicity from unchelated traces arising past week three)
I have to say I have a Triffid in the tank (3ft Crypt Balansae in the corner of a 12inch Cube and it drapes across the surface providing a large amount of shade for the Buce below, still throwing out new leaves), it has its feet in a small pot of tropica soil which has not stopped it reaching the other end of the tank with some daughter plants growing in inert substrate. So a significant amount of ferts probably end up in that monster.
If I was not on a shoestring budget and I could go to town on this I would be measuring and logging data 24/7 with Ion Selective Electrodes.
🙂
