plants pearl like crazy

[jaguarr]

Does anyone know why my plants pearl like crazy every time i do a little water change (about 10%).
They pearl if i dont add any water too, but just not as much.

thanks.

 

[Simpte]

Its common for plants to pear like crazy after a waterchange. Its usually a sign of not enough co2.

 

[Jchillin]

My specialty plants always pearl like that after a water change. I have no supplemental CO2, so it is not a worry for me. My L. Repens sometimes resembles an airstone.

 

[Hoovercat]

Tap water is often at or near O2 saturation. Adding it pushes the tank water nearer saturation. Thus, more of your plants respiratory O2 can't dissolve and becomes bubbles.

 

[jaguarr]

Tap water is often at or near O2 saturation. Adding it pushes the tank water nearer saturation. Thus, more of your plants respiratory O2 can't dissolve and becomes bubbles.

This seems reasonable.
So does it mean the plants grow just as much with no water change; it is because more O2 dissolves in the water that I don't see them pearl?

Thanks in advance.

 

[Hoovercat]

Yes

 

[malkore]

Tap water is often at or near O2 saturation. Adding it pushes the tank water nearer saturation. Thus, more of your plants respiratory O2 can't dissolve and becomes bubbles.

Winner! Between O2 and all the other trapped gasses in tap water, you'll see tons of false pearling the first 24 hours after a water change, particularly larger water changes. O2 and CO2 are the two common gasses in tap water.

 

[An t-iasg]

This must happen if you don't allow your tap water to age, right? I pour my water a day or two before a water change and let it age. I don't see any bubbles forming/rising in the tank - it's all been aged out by the time I do the water change. I see streaming for a while if I trim the top of a plant.

 

[malkore]

Correct, aged tap water releases the excess so you're no longer at saturation. You can still see some false pearling, but it's so much less dramatic that you're less likely to notice any change.

 

[sudz]

Is this also why you should let the tap water sit before testing it? CO2 would skew PH readings?

This would explain why i think my tapwater "bounces" around... I've Probably tested standing water. Ya learn something new every day!

 

[malkore]

Exactly sudz. some water companies end up with tons of CO2 in the water lines, so your fresh tap water may have a skewed pH..and you can tell because your tap will show something like 14ppm of CO2 when looking at the pH/Kh chart...but it'll quickly outgas down ot about 3ppm of CO2 and a proportionally higher pH.

When rested tap water pH is still lower than it should be for a given Kh (i.e. a combination that doesn't exceed 4ppm of CO2 per the chart)...then you know that some other buffer is present in your water, possibly a phosphate buffer. Because of this, you cannot use the Kh/pH chart reliably to determine CO2 levels. Not super common, but I've seen it a few times...a dKh of 11, but 48 hour aerated water has a pH of 7.2, which would be 19ppm of CO2...obviously not the true CO2 level.