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Hi guys, please do help me out here.

my ph is at 6.8 with a kh of less than 1? i don't understand.???

And when the co2 is turned on my ph is at 5.8. its too much for my plants.


will i just add baking soda? to solve my problem. about 1 teaspoon will increase my kh about 4 for a 50liter tank.
 

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It is likely that your water supply has very little buffering/kh so your tank kH is very low. To have a pH of 6.8 without CO2 implies your aquarium is slightly acidic ... do you use aquasoil or peat, etc which has the effect of lowering the pH of the water?

It is generally accepted that if you are using CO2 that you should maintain a kH value of 3 or higher, so that the pH high/low marks are more predictable. There is a danger of pH dropping too low otherwise (if kH is very low).

You should be encouraged to use the baking soda to increase kH. Do so in a careful manner; adding kH will cause pH to rise, and you do not want to raise your pH quickly.
 

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It is likely that your water supply has very little buffering/kh so your tank kH is very low. To have a pH of 6.8 without CO2 implies your aquarium is slightly acidic ... do you use aquasoil or peat, etc which has the effect of lowering the pH of the water?

It is generally accepted that if you are using CO2 that you should maintain a kH value of 3 or higher, so that the pH high/low marks are more predictable. There is a danger of pH dropping too low otherwise (if kH is very low).

You should be encouraged to use the baking soda to increase kH. Do so in a careful manner; adding kH will cause pH to rise, and you do not want to raise your pH quickly.
Thanks! just did add baking soda to my tank. hopefully it will change everything.

just using amazonia ADA soil with no peat soil at oil in the filter. just the ordinary stock in an Eheim filter.
 

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guys, do i need to those baking soda everytime because just the other day i dose it then i got a very good result with a kh of 4 degrees but apparently when i tested it again its back to 1 degree. help guys...
 

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It is hard to say what is going on. You have acidic properties (soil, etc) that are driving the pH down (and kH will follow down). Perhaps you can adapt to a lower pH and manage. What is your principal reason for wanting a higher pH (what symptom of the lower pH do you observe).
In theory you should be able to stabilize a higher pH using an alkaline buffer, but for you it seems you will be fighting to do this. It is up to you - you could keep trying to obtain higher kH to reach a better pH balance, or you could try to manage at the lower pH.
 

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i was thinking maybe this was the reason why my glosso plant are dying since the water is just too acidic. but they say i lacked light source. i just only have 30 LED watts for my 10 gallon tank.

heres the pic,

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I don't agree. The pH change is real. When anything in the water changes the acidity of the water the pH is a measure of that. Adding an acid, or something that is converted to an acid to any degree, as CO2 is, changes the surplus of H+ ions in the water, which is what a change in pH is. When you take a sample of the water in the tank and shake it up, you are removing the CO2, which also causes the amount of carbonic acid in the water to drop, reducing the surplus of H+ ions, as indicated by the rise in pH. Aquarium water pH is a result of several things in the water, it is a consequence of "stuff" being in the water. What harms fish is some of that "stuff", not the pH itself. (This is advanced chemistry explained by someone with only bare knowledge of any chemistry.):icon_cool
I would agree that CO2 injection does alter the _actual_ pH. CO2 reacts with water to form carbonic acid. CO2 + H20 -> H2CO3. H2CO3 dissociates in water into H(+)(aqueous) and HCO3(-)(aqueous). The H+ will raise the actual Ph, as the H+ concentration in water is the very definition of pH. However, This is a reversible reaction, and will eventually (even quickly) reverse. H(+) + HCO3 -> CO2(gas) + H2O. As for the effect on fish, I can't speak with any real authority.

I'm a non-practicing, but degreed chemist. :)
 
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