# lower pH with vinegar



## mafoo (28 Jun 2014)

My CRS tank's pH is still over 7 despite having colombo and 100% RO. I think the culprit is the landscape rock i had in it for a about 3 months when i first set up up a few years ago. Ive tried kapta leaves but its still over 7.

I was wondering if distilled vinegar would be a safe option to lower the pH of the tank?


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## EnderUK (28 Jun 2014)

Using any chemical to alter the pH is not recommend. I would think vinegar is a big no. It does sound like you have something in your tank buffering the water to neutral.


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## Nathaniel Whiteside (28 Jun 2014)

Its definitely not the '2 year ago landscape rock'. Id put money on it being the florabase, as its supposed to have a ph of ~6.5.

Whats your RO ph before you add?


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## mafoo (28 Jun 2014)

the ph is resolutely over 7.5 with forabase and loads of drift wood. Only ever use RO. Remineralise with salty bee shrimp.


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## Nathaniel Whiteside (28 Jun 2014)

So your ph comes out your RO machine ~ 7.5?


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## mafoo (28 Jun 2014)

Its neutral when i test it after ive remineralised it.

To give you some context, the tap water in this area generally comes out the tap at over pH 8


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## X3NiTH (28 Jun 2014)

mafoo said:


> Only ever use RO. Remineralise with salty bee shrimp.



In a 0dKH environment, strong aeration will degas CO2 beyond atmospheric equilibrium raising the pH above 7.


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## mattb180 (28 Jun 2014)

Vinegar goes better with fish.....


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## aliclarke86 (28 Jun 2014)

I'm not sure Nath. I can't keep pH down with syriu in the water.

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## mafoo (28 Jun 2014)

i think my mistake was landscape rock and co2 injection - I've been paying for it ever since.


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## Nathaniel Whiteside (28 Jun 2014)

aliclarke86 said:


> I'm not sure Nath. I can't keep pH down with syriu in the water.
> 
> Sent from my GT-I9505 using Tapatalk



Hey,
Yeah Ali, but i think, or it appears to me that mafoo was stating he had had landscape in there a while ago. Not currently


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## dw1305 (29 Jun 2014)

Hi all,
I'd agree with "EnderUK" and I really wouldn't recommend vinegar (although "100% distilled" (CH3CO2H(aq)), would be the one to use) or any other acid really. If you were keen on a weak acid, you could use citric acid (HOC(COOH)(CH2COOH)2), Wilkinson's sell it for home brew £1 for 50g, and it may act as a carbon supplement. It is a chelator, and it reduces TDS a bit.

I think the source of the buffering is the "Columbo florabase", it will have anion exchange capacity (AEC) (as well as CEC), and the ion exchange sites probably have a lot of HCO3-, Ca++ ions etc.. I'd try not re-mineralising the RO for a while and see what happens to the TDS and pH in the tank.

cheers Darrel


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## aliclarke86 (29 Jun 2014)

Nathaniel Whiteside said:


> Hey,
> Yeah Ali, but i think, or it appears to me that mafoo was stating he had had landscape in there a while ago. Not currently


Ah I see. That will teach me not to read before posting 

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## mafoo (2 Aug 2014)

dw1305 said:


> Hi all,
> I'd agree with "EnderUK" and I really wouldn't recommend vinegar (although "100% distilled" (CH3CO2H(aq)), would be the one to use) or any other acid really. If you were keen on a weak acid, you could use citric acid (HOC(COOH)(CH2COOH)2), Wilkinson's sell it for home brew £1 for 50g, and it may act as a carbon supplement. It is a chelator, and it reduces TDS a bit.
> 
> I think the source of the buffering is the "Columbo florabase", it will have anion exchange capacity (AEC) (as well as CEC), and the ion exchange sites probably have a lot of HCO3-, Ca++ ions etc.. I'd try not re-mineralising the RO for a while and see what happens to the TDS and pH in the tank.
> ...



So i put the RO in with half the minerals in (up to a tds of 80) on a 20% water change. pH went up to 8, all but 2 of the 10 CRS died.


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## dw1305 (3 Aug 2014)

Hi all,





mafoo said:


> So i put the RO in with half the minerals in (up to a tds of 80) on a 20% water change. pH went up to 8, all but 2 of the 10 CRS died.


Sorry to hear that. I'm really not sure at all why. 

My tanks run at about 60- 80 ppm TDS, mainly because that is about what our rain water arrives at. I usually ignore pH because as you get towards 0ppm TDS pH becomes more and more unstable. This is because pH is a ratio of the H+ ion donors and H+ ion acceptors, and as you move towards pure H2O you have smaller a small total amount of ions, so small changes in chemistry cause large changes in ratio and pH.

I'd be tempted to add some more dead leaves, or a chelator like EDTA, both of which would complex any heavy metal ions that might be present. 

cheers Darrel


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## mafoo (22 Sep 2014)

So after the remaining 2 crs snuffed it, i did the sensible thing and drained the tank and went and removed all the substrate. I put in florabase topped with their 'shrimp safe' black microgravel. I've conditioned the water with some blackwater extract / tropol, kapta leaves and after a month the ph has stabalised at 6.5.

I've had some cherry shrimp in there to test it out and they've been doing fine so i think it might be time to re-stock it.


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