# Can I make a neutral ph buffer with lye and peat?



## Fortuna Wolf (Feb 3, 2007)

My GF wants to keep tropicals in her tanks... these are all pretty much nano tanks... and she wants to use relatively high light to grow some pretty demanding plants. She loves her bettas. 

Anyhow, her water is rather hard and the ph out the tap is around 8.5. I got her some muriatic acid to lower it, but I told her that she should probably also buffer it, but since all the commercial buffers that I know of for ph 7-7.5 are phosphate based we don't want to use them. 

So, I got the idea of using humic or tannic acids as the weak acid part of the buffer solution. I've read that peat's tincture is relatively uncoloured, unlike wood or leaf tinctures, but retains the chelating and acidic properties. Can I make a strong solution of peat tea and then titrate to ph 7.0 with lye to make a decent buffer? 

I say lye because if I remember my high school chem right, the lye will react with some of the acids to form a salt, so that there will be a conjugate base of the acid, and therefore, a buffer solution. I figure that being a sodium salt plants won't be as eager to take it up as say, a potassium salt.


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## hoppycalif (Apr 7, 2005)

The much, much better solution to this is to ignore the pH. Plants and fish, with very few exceptions, don't care what the pH is, if it is between 5.5 and about 8. Just because it is easy to measure pH doesn't mean it is critical.


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## Squawkbert (Jan 3, 2007)

pH in planted tanks tends to drop over time anyway, so I'd just go w/ some peat in the filter or in another convenient place. This addition will hasten the process somewhat without altering the pH too quickly.


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## Fortuna Wolf (Feb 3, 2007)

Well, I made up a buffer solution, which came out to about .6g lye to bring 3 gallons of 5 ph peat extract up to ph 7.2. I went to the girlfriend's to test it out, and her tap water was back to ph 7. I love the city.


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## hoppycalif (Apr 7, 2005)

Your method for making a buffer solution does sound like it would work just fine, but adding that to a tank is not something I would do. The more things we add to the tank that are not consumed by the plants, the more potential problems we have. It is always best to minimize the substances we add, especially substances intended to alter the properties of the water. If there were a good reason to add something, that would be one thing, but altering the pH is not a good reason. (My opinion, of course.)


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## Fortuna Wolf (Feb 3, 2007)

Well, the point is to not alter the ph, its a buffer  

Another reason that I went with the peat extract is that I thought it could help plants by chelating metals and making them bioavailable.


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