Can Ph Change In Just One Day?

[EliteFishy]

Yesterday when I measured my pH it was 6.8. Today when I measured my pH it was 7.0. Can pH change this much in just one day?

 

[tttnjfttt]

pH can change based on your kH, or buffering capacity. As long as nothing has been added, i wouldn't worry about it too much.

 

[IovaykInD]

pH can change dramatically if you have c02. If you just have the normal stuff like filters and fish, it could be changing a bit. It will stabilize itself, and you don't have to worry about it. A lot of people only check their pH if they have plants in the tank. If you don't, no need to check the pH unless something looks wrong.

 

[Bignose]

In nature, pH will change during the day continuously, it is important for researchers to test at all different times and conditions. A small change in temperature can result in a significant change in the pH; and especially with plants, as noted above, CO2 can change pH, and with plants CO2 production is directly correlated with light. And almost no matter how bright your tank light is, is the sun is up through the windows the room and everything is a lot brighter than at night. Lastly, on my kit there is a color change between 6.8 and 7.0, but it is not super-huge. With the inaccuracies in the test kit itself (can you get exactly 5 drops all the same size every time?), a 0.2 change doesn't seem like much.

Ultmately, take several samples over several days, at the same time each day, and so long as it is all around the same point, your fish are fine.

 

[rdd1952]

As mentioned, a change of that nature isn't anything to be worried about but there are things that you could have added to your tank that would cause that. I'm not talking about chemicals which you should NEVER use to adjust pH. I'm speaking of things like rocks or certain types of substrate. Any rock that contains limestone will cause your pH to rise. Here is a very good thread that will help you along those lines. As I said, certain substrates contain crushed coral can can raise pH. They are mainly made for cichlid tanks where you need to keep the pH in th 8.0 range.