Potassium Carbonate

Latrell

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I recently made potassium carbonate from scratch and I wanna know the benefits of it in a planted aquarium and how will it affect fishes like tetras and guppies.
 

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I recently made potassium carbonate from scratch and I wanna know the benefits of it in a planted aquarium and how will it affect fishes like tetras and guppies.
I don't think it's a good idea to just add kco3 to a tank with fish in it unless you have tested it's effect on the water several times beforehand and know exactly what you are doing. It will raise your KH and pH significantly and instantly and could demolish every fish in the tank. It's easy to make fertilizers but the trick is making them safe for fish. What is the concentration of kco3 per gram and how much do you need to actually benefit your plants? Do they need those particular nutrients?
 
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Latrell

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I don't think it's a good idea to just add kco3 to a tank with fish in it unless you have tested it's effect on the water several times beforehand and know exactly what you are doing. It will raise your KH and pH significantly and instantly and could demolish every fish in the tank. It's easy to make fertilizers but the trick is making them safe for fish. What is the concentration of kco3 per gram and how much do you need to actually benefit your plants? Do they need those particular nutrients?
Thanks that really helps alot im still working out the measurements atm I can see 1/2 TSP of the solution dissolve in water at 1TBS...can treat 5 gallons of water .....yea i have a spare 5 gallon with some trimmed plants in it and in a week Imma check the results
 

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Thanks that really helps alot im still working out the measurements atm I can see 1/2 TSP of the solution dissolve in water at 1TBS...can treat 5 gallons of water .....yea i have a spare 5 gallon with some trimmed plants in it and in a week Imma check the results
Check the effect of the kco3 ON THE WATER, not just the plants. Check changes in the water chemistry. It might be great for the plants but deadly for your fish. If you have a chemistry teacher in your school, consult with him/her. Teachers can be a great source of help and information.
 

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What are you trying to achieve? Your profile says your water is on the hard side, if so why are you trying to make it even harder? What are your current PH, KH and GH values?

Unless you know these values you should not experiment with anything that can make your water into liquid rock, if it is very hard already or if you add too much. Happy to help you with some calculations for K2CO3 but you need to provide your current values and your target values otherwise we can't guide you safely.

Very hard (Liquid rock) water only benefits African cichlids and not any of your fish or plants so you want to avoid that happening.
 
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Latrell

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What are you trying to achieve? Your profile says your water is on the hard side, if so why are you trying to make it even harder? What are your current PH, KH and GH values?

Unless you know these values you should not experiment with anything that can make your water into liquid rock, if it is very hard already or if you add too much. Happy to help you with some calculations for K2CO3 but you need to provide your current values and your target values otherwise we can't guide you safely.

Very hard (Liquid rock) water only benefits African cichlids and not any of your fish or plants so you want to avoid that happening.
I understand .......I was just wonder bc new york tap water is on the soft side so I was gonna use it as a fertilizer for a 40 gal breeder I'm setting up and asking how will it affects the fish
 

fa4960

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K2CO3 is not a fertilizer. Although it will add some potassium to your tank it is the carbonates that makes all the difference with this chemical. In our freshwater hobby it is solely used by people you want/need to raise the PH and KH. If you don't know how soft your water is as a starting point how are you going to set a target and calculate how to reach it?

I suggest you either find a LFS that can test your water for you, or buy a PH as well as KH/GH test kit. You may also be able to get a test sheet from your local water authority that will tell you what you need to know about your tap water. Just keep in mind that your tank water may vary from your tap water depending what you have in your tank in terms of substrate, wood etc.

If you want to learn about water chemistry this is a good link:

PH KH GH and TDS: What matters for planted aquarium?
 
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Latrell

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K2CO3 is not a fertilizer. Although it will add some potassium to your tank it is the carbonates that makes all the difference with this chemical. In our freshwater hobby it is solely used by people you want/need to raise the PH and KH. If you don't know how soft your water is as a starting point how are you going to set a target and calculate how to reach it?

I suggest you either find a LFS that can test your water for you, or buy a PH as well as KH/GH test kit. You may also be able to get a test sheet from your local water authority that will tell you what you need to know about your tap water. Just keep in mind that your tank water may vary from your tap water depending what you have in your tank in terms of substrate, wood etc.

If you want to learn about water chemistry this is a good link:

PH KH GH and TDS: What matters for planted aquarium?
Thanks this link helps me understand more about kh and ph and the affects on my plants and fishes....most likely Imma hold off my experiment for awhile till a get a test kit but Imma still try out mini test on my spare 5 gallon.
 

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I understand .......I was just wonder bc new york tap water is on the soft side so I was gonna use it as a fertilizer for a 40 gal breeder I'm setting up and asking how will it affects the fish
New York has amazingly good soft water. You might want to change your "it's on the hard side" statement in your profile. If I were you, I'd just get a commercial fertilizer that doesn't change your pH and take advantage of that incredible natural water that you have! You could have some amazing fish in that water-like Discus! Luckeeee! I am limited by my 8.2 pH and GH of 360+ to only the hardest water species-African Cichlids etc.
 
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Latrell

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New York has amazingly good soft water. You might want to change your "it's on the hard side" statement in your profile. If I were you, I'd just get a commercial fertilizer that doesn't change your pH and take advantage of that incredible natural water that you have! You could have some amazing fish in that water-like Discus! Luckeeee! I am limited by my 8.2 pH and GH of 360+ to only the hardest water species-African Cichlids etc.
Oh okay thanks
 

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I've used potassium bicarbonate (KHCO3) for my planted tanks with fish, based on a Aquavitro product named "KH carbonate for plants- raises carbonate hardness KH, increases potassium".
I inject CO2 and I was concerned about fluctuating pH, therefore I decide to increase my KH while adding K for my plants.
OP is asking about carbonate, not bicarbonate so ... if someone can explain the difference between the two when dissolved in the water (hint: CO2 present), I'll add some more info.
I am expecting a raise in pH when K2CO3 is added. Guppies should be fine, don't know about tetras. GH, the way we measure it, should not be affected. KH will raise but that does not have a direct impact on the fish.
 

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OP doesn't seem to be concerned about fluctuating PH?

Potassium carbonate (K2CO3) is a stronger base (alkali) than potassium bicarbonate (KHCO3), because both its potassiums are replaceable with hydrogen whereas in the bicarbonate one has already been replaced. The bicarbonate form is "safer" and so much more readily available.

There is at least one article claiming that Potassium Carbonate remove CO2 with Boric Acid as a promoter...

Absorption of carbon dioxide into aqueous potassium carbonate promoted by boric acid - ScienceDirect

Whether this actually happens in our aquariums I can't confirm but what I do know is that any Carbonate compound will increase KH and therefore also PH. My suggestion to OP in the previous posts is to carry out his "experiment" in a controlled manner, i.e. know your starting point, know your target and calculate how you get there. To me this is the safe way for especially fish but also plants for that matter.

However if OP just "randomly" wants to add some K2CO3 to his tank then Rotalabutterfly will (as almost always) help.

If OP want to raise KH 15 ppm in 5 gallons of water you add 6.99 g K2CO3 (if you have KHCO3 then add 10.13 g). However no idea how to estimate the raise in PH that will follow, other than a PH raise will happen.....
 
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Latrell

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OP doesn't seem to be concerned about fluctuating PH?

Potassium carbonate (K2CO3) is a stronger base (alkali) than potassium bicarbonate (KHCO3), because both its potassiums are replaceable with hydrogen whereas in the bicarbonate one has already been replaced. The bicarbonate form is "safer" and so much more readily available.

There is at least one article claiming that Potassium Carbonate remove CO2 with Boric Acid as a promoter...

Absorption of carbon dioxide into aqueous potassium carbonate promoted by boric acid - ScienceDirect

Whether this actually happens in our aquariums I can't confirm but what I do know is that any Carbonate compound will increase KH and therefore also PH. My suggestion to OP in the previous posts is to carry out his "experiment" in a controlled manner, i.e. know your starting point, know your target and calculate how you get there. To me this is the safe way for especially fish but also plants for that matter.

However if OP just "randomly" wants to add some K2CO3 to his tank then Rotalabutterfly will (as almost always) help.

If OP want to raise KH 15 ppm in 5 gallons of water you add 6.99 g K2CO3 (if you have KHCO3 then add 10.13 g). However no idea how to estimate the raise in PH that will follow, other than a PH raise will happen.....
Thanks a lot . Imma read the article in a bit
 
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