Potassium Carbonate - kh / ph

[Delapool]

I saw this can be used to lift kh. Does anyone use it? I found one supplier.

I don't know if it is because of a ph of 7.5 or so but my kh drops faster then seashells and cuttlefish can fix.


Potassium carbonate - The Free Freshwater and Saltwater Aquarium Encyclopedia Anyone Can Edit - The Aquarium Wiki

 

[mrvincent]

No plz DONT !!! Potassium carbonate contains much more potassium than carbonate. Use bicarbonate sodium instead or carbonate calcium !!!

I would only do it to raise KH a very little if I had heavy planted tank with high light and CO2. You can cause more harm than good by doing this.

Calcium raise both KH and GH, sodium bicarbonate only raise KH.


I mean, potassium carbonate rising KH is more a side effect...

 

[Delapool]

No plz DONT !!! Potassium carbonate contains much more potassium than carbonate. Use bicarbonate sodium instead or carbonate calcium !!!

I would only do it to raise KH a very little if I had heavy planted tank with high light and CO2. You can cause more harm than good by doing this.

Calcium raise both KH and GH, sodium bicarbonate only raise KH.


I mean, potassium carbonate rising KH is more a side effect...

Drat, thanks for the info. I'm using some aquarium product at the moment which is plant safe and keeps kh above 2 but was hoping to get something cheaper. I was worried that sodium carbonate would harm plants? (worse than the fish that is ). I'll look into calcium carbonate? Tank ph is about 7.3 and kh is 2 and dropping. Ph is fine - not worried about any changes, kh seems to drop like mad over summer.

 

[mrvincent]

I don't understand how your KH drops... you mean the tap kh is dropping ? You must buffer the water before you put it in tank when doing waterchanges, or it will cause stress du to fluctuating PH.

 

[Delapool]

I don't understand how your KH drops... you mean the tap kh is dropping ? You must buffer the water before you put it in tank when doing waterchanges, or it will cause stress du to fluctuating PH.

Yes, tap kh is 5 and tank kh is mostly 2 the next day after a 50% pwc. Driftwood, plants, stocked tank - I guess it just gets used up.

Tank ph is fairly steady but I cheat and add a plant-safe buffer to keep the kh from dropping further. However that's a bit expensive so I was going to buy the buffer from a supplier but I don't know what it is.

It seems to be a summer problem. Over winter the water changes keep pace. Plus I've added more driftwood lately.

 

[enrgizerbunny]

I wouldn't use it. It will make your PH skyrocket.

 

[Delapool]

Sigh, thanks - I don't need ph up. Oh well. I'll have to find out what the shop product is - can't find anything for ingredients.

 

[mrvincent]

Sigh, thanks - I don't need ph up. Oh well. I'll have to find out what the shop product is - can't find anything for ingredients.

Just use normal Arm & Hammer as I do, it cost 1-2$ at the grocery.
Just use very low quantities to raise KH, half teaspoon is really enough for a 10g. Raise it slowly, mesure it, so you'll know how much it take to raise of how much dKH°

 

[Delapool]

My only concern is if baking soda is fine in a planted tank? I read conflicting information.

Thanks for picture, much appreciated.

 

[mrvincent]

It's planted tank safe. Just check my tank, I raise KH via baking soda.

 

[Fishfur]

If you are worried that the sodium in the Bicarb will harm the plants, it won't. Mr. Vincent is quite right, the amounts you would use to raise KH won't harm the plants at all. But do be careful, use only a small amount and measure to see how much change you get, so you'll be able to figure out the optimum dosage to use.

 

[Delapool]

Wow, nice tank.

Thanks all for the information, yes I just want to tweak it up a few dh. This sounds much kinder on the wallet.

 

[GMDemo]

Any Bicarbonate will raise your PH level but lets take a look at the problem in hand and solutions.
Plants require a balanced diet of NPK as do most living organisms (if not all). One of the most famous organic balanced fertilisers is blood fish and bone and just by looking at this we know that fish require both Potassium and calcium. Lets have a look at the various chemicals suggested above;
1) Sodium bicarbonate (baking soda, bicarbonate of soda) NaHCO3 this contains sodium (not good for fish or plant) and Bicarbonate will raise your PH
2)Potassium bicarbonate KHCO3 (good for fish and plants) will raise your PH
3) Potassium Carbonate K2CO3 good for fish and plants will not raise your PH levels unless acid is present ie a PH level of less than 7
4) Calcium carbonate CaCO3 good for fish and plants this adds both calcium and carbonate so will higher both GH and KH but will only raise PH if there is acid present.
If your KH is below 4 you are liable to have PH crashes but it will also cause problems with your good bacteria so you may well end up with spikes in your
ammonia and Nitrite levels.

I am aware this thread is old but it still comes up in google so I felt it necessary to post

 

[enrgizerbunny]

Any Bicarbonate will raise your PH level but lets take a look at the problem in hand and solutions.

Plants require a balanced diet of NPK as do most living organisms (if not all). One of the most famous organic balanced fertilisers is blood fish and bone and just by looking at this we know that fish require both Potassium and calcium. Lets have a look at the various chemicals suggested above;

1) Sodium bicarbonate (baking soda, bicarbonate of soda) NaHCO3 this contains sodium (not good for fish or plant) and Bicarbonate will raise your PH

2)Potassium bicarbonate KHCO3 (good for fish and plants) will raise your PH

3) Potassium Carbonate K2CO3 good for fish and plants will not raise your PH levels unless acid is present ie a PH level of less than 7

4) Calcium carbonate CaCO3 good for fish and plants this adds both calcium and carbonate so will higher both GH and KH but will only raise PH if there is acid present.

If your KH is below 4 you are liable to have PH crashes but it will also cause problems with your good bacteria so you may well end up with spikes in your

ammonia and Nitrite levels.



I am aware this thread is old but it still comes up in google so I felt it necessary to post

Yes the thread is ancient but I have to disagree with you.

Anecdotal, but adding potassium carbonate raised my pH about double or more that of sodium bicarbonate. I use calcium carbonate in my filter to buffer my pond (like 5 gallons of oyster shells) and it raises my pH- albeit slowly and keeps it steady because calcium carbonate is not very soluble in water. I used crushed coral in a cut/tied women's legging as a buffer in my aquarium and I only added baking soda to my change water to prevent swings. PH out the tap is <6, but rises to 7 after 24 hrs with 0gh/kh.