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Baking soda to increase KH ?

eminor

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Hello, i use rain water and i want to increase the KH to 2, can i use baking soda which is NahCO3 i think to increase dKH ? is it safe for plants ? thx
 
I advise against it. You would be adding sodium which is not good in software tanks although to be fair it wouldn't be that much. (~4ppm). If I was you I would go for KHCO₃ (potassium bicarbonate). If you insist on using NahCO3, you need to remineralize the water beforehand. Don't go and add it to the tank or you will end up having some PH swings momentarily.
 
What @Hanuman said. Adding sodium at much above trace levels to a tropical freshwater tank is generally a bad idea. In my low-tech, I remineralize my RODI water with a small amount of Potassium Carbonate (K2CO3) which gives me just below 1 KH and about 12 ppm of Potassium (K) which I don't get much of with my macro fertilizers otherwise.

Cheers,
Michael
 
Hello, i use rain water and i want to increase the KH to 2, can i use baking soda which is NahCO3 i think to increase dKH ? is it safe for plants ? thx
I have used both, baking soda - sodium bicarbonate and potassium bicarbonate, and at the time was going for 3 KH. Did not notice any difference in plant growth. Once I ran out of potassium bicarbonate I switched back to baking soda. I now go for a 1KH in all my tanks and use an inert substrate "BDBS".
Before I went to RO I used my tap water "aka liquid rock" with 94ppm of sodium and still was able to grow almost everything.
 
Before I went to RO I used my tap water "aka liquid rock" with 94ppm of sodium
If your running your water through a softener using NaCl then 94 ppm is about what to expect depending on the ion exchange rate. For straight city water 94 ppm would be far above EPA levels. Before using RODI water I switched over to KCl in our softener which only spikes the Potassium levels and it's slightly more costly. We still use KCl but, I run it through the RODI unit.

Cheers,
Michael
 
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If your running your water through a softener using NaCl then 94 ppm is about what to expect depending on the ion exchange rate. For straight city water 94 ppm would be far above EPA levels. Before using RODI water I switched over to KCl in our softener which only spikes the Potassium levels and it's slightly more costly. We still use KCl but, I run it through the RODI unit.

Cheers,
Michael
No you are incorrect. My water is not softened and the tap water has 94ppm sodium. According to the water authority sodium is a " not regulated" substance.

View attachment 1663960736468.png

The EPA does not regulate the amount of sodium in tap water, they only have a suggestion of optimal levels.
Screenshot 2022-09-23 at 12-22-02 Document Display NEPIS US EPA.png
 
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I used my tap water "aka liquid rock" with 94ppm of sodium and still was able to grow almost everything.
Would you kindly name some species? I've been planning to test sodium tolerance of various aquatic plants, and a possible effect on K,Mg,Ca uptake, but more urgent issues make me postpone it over and over.
 
No you are incorrect.
Well, thats because you assumed I meant legal as opposed to recommended ;)... Sodium is not regulated, but 94 ppm is definitely far above the recommend levels. And 94 ppm would certainly be 10-40 times above the levels you will find at natural habitats for most of our plants and fishes. 2-4 ppm is not uncommon in the Amazon basin - some areas (such as the Jurua river) as much as 10 ppm.

As @_Maq_ points out, it would be interesting to know what specific plants - among the almost everything - you have been able to grow at 94 ppm of Sodium.


Cheers,
Michael
 
Would you kindly name some species? I've been planning to test sodium tolerance of various aquatic plants, and a possible effect on K,Mg,Ca uptake, but more urgent issues make me postpone it over and over.
Bacopa -Carolinana,Colorata, and monnieri. Vallisneria Spiralis "Leopard". Nymphoides Aquatica. Staurgyne Repens. Anubias Nana. Heteranthera Zosterifolia. Ludwigia Super Red, Rubin. Myriophyllum Rorima. All grew very well for me. The rotala everything and altermanthera everything did not grow well or as well as I would of liked.
 
Before I went to RO I used my tap water "aka liquid rock" with 94ppm of sodium and still was able to grow almost everything.
Seems strange that someone would suggest an outlandish situation where plants can grow and people doubt it.
I once spoke to a one eyed parrot that told me high nitrate and bad ratios wouldn't work, surfiice to say the parrot no longer has one eye. 😁
 
Well, thats because you assumed I meant legal as opposed to recommended ;)... Sodium is not regulated, but 94 ppm is definitely far above the recommend levels. And 94 ppm would certainly be 10-40 times above the levels you will find at natural habitats for most of our plants and fishes. 2-4 ppm is not uncommon in the Amazon basin - some areas (such as the Jurua river) as much as 10 ppm.

As @_Maq_ points out, it would be interesting to know what specific plants - among the almost everything - you have been able to grow at 94 ppm of Sodium.


Cheers,
Michael


If your running your water through a softener using NaCl then 94 ppm is about what to expect depending on the ion exchange rate. For straight city water 94 ppm would be far above EPA levels. Before using RODI water I switched over to KCl in our softener which only spikes the Potassium levels and it's slightly more costly. We still use KCl but, I run it through the RODI unit.

Cheers,
Michael
Well my response was accurate to what you posted. " For straight city water 94 ppm would be far above EPA levels." You said nothing about recommended levels. The water report is for my area in Southern California but if you look a water reports from Los Angeles to San Diego it is consistent with my area. Millions of people use this water for aquariums and grow fish and plants just fine.
However I do agree RO water reminerlized to Low KH levels is the way to go and I find it much easier to grow whatever I want.

Oh Cabomba Frucata grew fine but "leggy" in comparison.
 
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@RLee2 The fact that you have grown plants in sodium infused waters in your tank does not equate it being a good thing for plants. Sure plants will grow, but to some extent and as you have experienced you had issues with plant species like rotalas and co. Also Your 3dKH of sodium bicarbonate is indeed not that much Na (~24ppm). Here in Bangkok, tap water is at ~22ppm but it can rise dramatically to levels about 1000ppm during the dry season. There doesn't seem to be any recommended higher limit, at least where I am.

At the end of the day it's better if you don't have sodium or very little quantities in the tank since plant can only use it at trace levels. Can they tolerated more to a certain extent, sure, but is it a good thing, no, specially if you have many sensitive plants.

Millions of people use this water for aquariums and grow fish and plants just fine.
That seems a bit of an excessive number, but yes I am pretty sure many people that have tanks use tap water. In fact, having some sodium is a good thing for certain fresh water fish. Here in Thailand some add Na to their beta tanks.
 
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@RLee2 The fact that you have grown plants in sodium infused waters in your tank does not equate it being a good thing for plants. Sure plants will grow, but to some extent and as you have experienced you had issues with plant species like rotalas and co. Also Your 3dKH of sodium bicarbonate is indeed not that much Na (~24ppm). Here in Bangkok, tap water is at ~22ppm but it can rise dramatically to levels about 1000ppm during the dry season. There doesn't seem to be any recommended higher limit, at least where I am.

At the end of the day it's better if you don't have sodium or very little quantities in the tank since plant can only use it at trace levels. Can they tolerated more to a certain extent, sure, but is it a good thing, no, specially if you have many sensitive plants.


That seems a bit of an excessive number, but yes I am pretty sure many people that have tanks use tap water. In fact, having some sodium is a good thing for certain fresh water fish. Here in Thailand some add Na to their beta tanks.
I think this discussion has gone some what astray. I am not promoting the heavy use of sodium. I agree that sodium at higher levels can cause issues. The OP asked if raising his KH to 2 with baking soda was ok for his plants and it is.
Southern California has roughly 24 million people so ya no way there are millions of aquarium enthusiast.........but enough to make my point.
 
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Actually, farmers' literature knows plants which rather like some sodium in their nutrition and take it up in no small amount. But relevant data for water plants are missing. I wonder perhaps some plants stemming from (eastern) Africa rank among them. Some of us observed rather strange behaviour of some Ammannias. I'd like to know what their response to sodium would be.
Unfortunately, like I said, I haven't got capacity to test it, yet.
 
Funny thing is that i was making NahCO3 + Cacl2 + MgSO4 solution in a small container before dosing in my aquarium

i didn't know ( i did in shcool back then ) that NahCO3 + Cacl2 would make a reaction, if i understand well the small explosion was CO2 and the result is CaCO3 ? is that right, thx

so far no problem with plants
 
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