| | Re: Method of controlled imbalances and gda...
d) Ca, K y Sodium carbonates
There is a dificul solution issue about adding carbonate to the water of a planted aquarium. It almost an intuitive assert to add potassium of calcium carbonate or bicarbonate.
However, we shouldnít take attention to the total amount of K we are adding to the water. If we add potassium phosphate, nitrate and carbonate or bicarbonate, we will can easily be adding like 50 ppm of K. If we also add potassium sulphate, then the amount of K is too high. K by it self is not an issue like iron that can became poisonus in high dozes but it can produce that the No3 reach zero and that would be a problem.
If we dont want to add so much K, then the solution is to combine Cacium, sodium and potassium carbonates/bicarbonates in order to keep all of them in acceptable rates.
As I already explain in the Ca/Mg chapter, we should be carefull with the amount of Ca we add if we donít want to have issues with red algae or GD.
On the other hand, discus an apistos are sensitive to Ca.
The reason for adding carbonates to the water is related to avoid a breakdown of the buffer that allow the PH to fall to much.
I was born in Buenos Aires City, in Argentina. We live in just besides the De La Plata River wich borns in the Mato Groso swamps in Brazil. The tap water has 1.5 kh and barely no Ca. I never had problems with this myth about the breackdown of the buffer. Even the PH can fall, this is not a never ending fall. Only fish from hard water and high ph have serious problems. Botia macracanta is one of them.
I am not suggesting to have a 5.5 ph with our fish, I am just triyng to explain that this is not such a big deal.
We have this very soft water and hobbist have successfully been using aragonite for decades to avoid this buffer breakdown. Aragonite, coral sand, is thicker than the standar calcium carbonate we can buy. The advantage of this is that the water wonít become white and as soon as its low water dissolving properties, the Co2 will dissolve it slowly when this is need and no more.
We only need a small amount of aragonite in our filter.
The MCI Works with only 0.1 ppm of Fe per week.
The PPS and the EI uses higher levels of Fe. Fe reduces the redox potential and It could be useful if you have too much sulfur in your water or it is pollutioned. On the other hand, if you have both, Po4 and Fe high, they will become iron phosphate.
There is a lot of debate about if plants can uptake it or not. It doesnít make any difference. You can know how much Fe are your plants uptaking if you like adding 0.025 a day until you get algae. I believe that this is not necessary, but you can do it if you feel like. The algae that will bloom for Iron can be stoped with the Kno3 generic protocol but you will need gluta to eliminate them.
However, I believe that the best is to add Po4 and Fe in alternating days. In my experience, 0.1 ppm of Fe is enough. Anyway, your plants will tell you if you really need more.
I know that it is a fact that you can have higher levels of Fe in your tanks with no algae, but I also know that this is less stable and there is no need for that. Plants will not start starving if you add Fe in a more efficiently way.
But It is all about to focus, donít mix method. You can add less Fe only if you add less Po4. As I explain before, it is all about imbalances instead of lack or excess.