# pH too low?



## peterl (Nov 27, 2006)

What might cause very low pH?

My tap is pH 8. The water in my 20 gal. long (30 inches) has the following parameters:

pH	< 6 (5)
Ammonia (ppm)	0
Nitrite (ppm)	0
Nitrate (ppm)	0
KH (Â°dKH)	1
KH (ppm)	17.9

The tank is moderately planted, 3M CQ sand, big chunk of driftwood, 5 Sterbai corys, 8-10 C. pygmaeus, a handful of tiger shrimp.

pH 5 is the lowest I can measure with either a chemical test or a dip strip. I have a feeling that it is really close to 5, definitely way under pH6.

I do 30-50% water changes weekly. The corys spawn regularly, but not successfully.

I know I was overfeeding for a while, but I stopped. My theory is decaying plant matter. The pH in my 15 gallon shrimp and oto tank is 6 (and my otos are still spawning like crazy!)

FWIW, my 55 gal. (4 foot) tank which is heavily planted has 0 ammonia, 0 nitrates, and 0 nitrites, too.

TIA,

Peter


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## gage (Feb 7, 2007)

driftwood has a tendency to cause low PH problems, curse them dam tanins.


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## edburress (Jun 9, 2007)

My initial reaction is that one of your test kits is reading incorrectly. kH of 1* is usually associated with pH in the 5-6.5 range. Does your tap water test at pH 8 and kH 1? That would be really strange, but sometimes tap water drops naturally, so you can test your tap water, let some sit for 24 hours and retest. It is possible that your tap water drops without any buffering from driftwood, etc.

If your kH is 1, it is possible (like gage said) that the driftwood is dropping your pH significantly, but water with a higher kH normally won't swing that much.

I'd try and get a second test of your kH and Nitrate. Nitrate shouldn't be 0 if the tank is established. But I've had experiences where it would still test at 0 for up to 6 months in planted tanks, but that is probably just inaccuracies of my test kits.

but regardless, IMO the corys prefer pH 6 more than pH 8 so if they are spawning I think they are happy :thumb:


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## Barbie (Feb 13, 2003)

kH is the water's ability to maintain a stable pH. You can definitely have 1 degree and a high pH to start with. It just won't be stable there, as you're seeing now. No nitrates in a planted tank area also totally within normal realms of being possible. I dose nitrates in my 92 gallon corner bow and even with all of the fish in there still can't get a reading by the next day.

The tannins from the driftwood would definitely be enough to push 1 degree of kH over the edge to pH crashdom. I would recommend a shell or two in your filter, or even some large chunk crushed coral (it doesn't take much!). If your water starts to become more acidic, it then dissolves the coral faster, raising the pH again. If your tap is already coming out at 8, that shouldn't happen immediately, and you'll have a much easier time providing stable water parameters.

Barbie


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## PsYcHoTiC_MaDmAn (Dec 26, 2005)

ironically, despite having a KH of 1/4 (5ppm) I cannot get my pH below 7

comes out the tap at 7 and stays there. despite bogwood. I need to try peat. but haven't been able to get any yet


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## Number6 (Mar 13, 2003)

PsYcHoTiC_MaDmAn said:


> ironically, despite having a KH of 1/4 (5ppm) I cannot get my pH below 7
> 
> comes out the tap at 7 and stays there. despite bogwood. I need to try peat. but haven't been able to get any yet


 There are things out there that don't read on a KH test but still buffer the water...

might want to look into the rarer buffering agents!


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