Why do my plants pearl after water changes, and only then?

[ingg]

Help a newbie understand.

I can literally make java moss pearl. I know it isn't trapped bubbles from the water change splash, I can watch them form.

Every tank.

And after it is done, it doesn't happen again... no ferts during the week, maybe this is it?

I'm trying to understand how to better treat plants...

My water changes are growing from the 10-15% fish need to the 30-40% plants need.

I'm slowly working my way into CO2, DIY systems for now, the cost is prohibitive to a peaceful spousal coexistance to go pressurized (And none of the tanks are the the same rooms, so it is a hefty cost).

I'll be ordering ferts once Greg Watson's old company has Plantex back in stock, supposed to be next week (and oh boy will I have lots of questions then).

This is one that puzzles me every week, tho... every week, they pearl, grow like nuts a day or two, then stagnate, until the next water change...


EDIT IN

Literally. Java moss pearling:

[Jeff120]

You are introducing lots of O2 when you do water changes, hence the pearling, I bet your glass pearls as well.

When plants pearl for real the water is supersaturated with O2, the plants are giving off lots of O2, this happens most often with fast growing stems, your water changes are doing this for you.

Dont worry if you plants never pearl, it dosent really mean anything if they dont. Ferts and CO2 will help the plants grow to their maximum ability and then you will get some real pearling

[krisw]

Well, I don't know if I have a scientific explanation besides my own understanding that gases are compressed from being under pressure in your pipes, which are then release once in the tank.

The main thing that is often confused is the belief that pearling equals healthy plants. This can be the case, but isn't necessarily so. You can maintain wonderfully healthy plants without seeing any pearling. I would say that if you see great growth for 1-2 days after a water change, that can be attributed to the plants using up the available nutrients from the water column. If you're injecting CO2 (DIY or not), and you're not dosing any ferts, then this is fairly expected behavior. Once you start dosing, you should be able to see continued growth throughout the week. You may or may not see pearling, but you should have healthy plants.

[Ben Belton]

Plants can be healthy and not pearl, but they sure are pretty when they do.

[John G]

This has been discussed quite a bit n the Aquatic Plants Mailing List. See, e.g., http://fins.actwin.com/aquatic-plants/m ... 00151.html If you search there on "pearing after water changes" you'll find quite a few theories on it.