What causes pH to change?

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noncentric

Aquarium Advice Activist
Joined
Mar 6, 2006
Messages
115
Location
Western WA
I'm trying to get a list of the different things that cause the pH of freshwater tanks to change. Things other than chemicals - like pH up and pH down.

What types of things cause pH to rise?
- crushed coral in filter
- ???

What types of things cause pH to drop?
- CO2 injection
- peat moss in filter
- ???

Thanks. :)
 
ph to rise:
crushed coral, limestone, baking soda, and others.

ph to lower:
peat, driftwood, CO2, and a few others.
 
Co2 will cause the biggest drop in PH. Now remenber with Co2 once the Co2 starts running out the PH level will start to raise back up. Now driftwood will cause the next biggest drop in PH level usaully around 1.5 to 2.0ppm depending on the size of the peice of wood the more it will drop. But I'm not sure on what the total amount the PH will drop with a larger peice in the tank. I have a singel peice 24'' long and about 10 to 12 '' around in my 75gal and it drops the PH 3.5ppm and as long as the driftwood is in the tank the PH level will stay there.Til you cjanges the water and it has to start over droping it. LOL
 
I haven't noticed a change at all with the driftwood in regards to pH. Peat will cause a major drop. I had it drop about 1.8 in a matter of 45 minutes. It may have dropped below that by the test kit only went to 6.0.
 
Any type of limestone rocks will cause pH to rise, same as crushed coral, seashells, etc.

Biological activity will cause pH to drop over time, if there's nothing to buffer the water. Even if the water is hard/alkaline to begin with, the buffering compounds will break down, and pH will drop. Once it becomes established at a lower value, it will maintain it even with water changes, if not done often enough.
 
Almonds and almond leaves, and many other leaves will cause the ph to drop. It only took one almond with shell to drop my 2.5 gallon from 7.8 to 7.2 for my betta.
 
I have had great success with the use of house hold acids. i.e. vinegar, which must be distilled white, as well using orange peal slices in the storage water under a neutral rock, like shale. Then add the water from the storage container to the tank during water changes. As well Reverse Osmosis water also lowers ph by decreasing the buffering ability of your current tap water. Just google lower ph in water and all of these methods and more will show up. I think there was 6 million hits 8O good luck!
 
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