Why water change day seems to grow aquatic plants better

denske

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Tom Barr;119372 said:
Another thing to consider: how does plants tell if they are submersed or not? Hint: it involves a gas, not one we typically discuss on plant forums, but is well researched.
This gas may also have a positive effect on growth if it's suddenly removed.

What gas are we talking about here? Hydrogen?
 

Tom Barr

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http://www.prirodni-akvarium.cz/en/index.php?id=en_algaeTOC

I'm inclined to agree with the hypothesis. I used as different method in the past that I think is highly effective for the loading rates.
I added progressively more and more fish slowly, to a high light well run aquarium. Until, you guessed it, algae.
The patterns I saw: Green water was 1st, then BBA, then Staghorn.
Same thing when I uprooted a lot of jobes sticks in the sediment.

This led me to hypothesize that NH4 was the cause. This was false however as we can dose NH4 at relative low levels, ADA As has a fair amount as do soils etc and not get algae issues.
If the CO2 is slightly poor/not optimal, and you add NH4, then you can get Green water, but the others? Not so much.

A standardized method to to progressively and slowly increase the loading rates in a well run panted tank is the key to the methods.
I think adding progressively small sized fish can accomplish this easily and relatively cheaply, eg, you could use bait minnows or guppies etc. You need to feed them so the amount of food needs to be considered also and type.

Measuring COD is not easy, you need a heating block or a water bath. So it cost more than many other methods. But not as bad as a lot of things.
I've been meaning to do this for sometime and I think Jeffery got me going again when I'd put it on the back burner.
Doing mesocosm and bench scale test, then seeing how well that data correlates to existing field data would be a nice support for looking at getting a grant to do a manipulative research project in the field.
 

gsjmia

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Tom, I just read the article and saw this:

In contrast, in tanks, where we used Lewatit (anion exchange resin, which removes anions of inorganic acids and anions of humic and organic compounds from the water, and replaces them by anions of chloride), the plants were lush, completely free of algae and cyanobacteria, which were not even on the aquarium glass.

I looked up lewatit and its for sale on the German Ebay for not much $$, could such filter be made using an old style diatom filter with these beads?

Would it be worth pursuing?

About 5 years ago I put a Vortex diatom filter on my 46gal with DE powder and it got clogged/dirty overnight.

What about something the size of that Ocean Clear cannister filter you were selling?

- - - Updated - - -

Tom, I just read the article (great website) and saw this:

In contrast, in tanks, where we used Lewatit (anion exchange resin, which removes anions of inorganic acids and anions of humic and organic compounds from the water, and replaces them by anions of chloride), the plants were lush, completely free of algae and cyanobacteria, which were not even on the aquarium glass.

I looked up Lewatit and its for sale on the German Ebay for not much $$, could such filter be made using an old style diatom filter with these beads?

Would it be worth pursuing?

About 5 years ago I put a Vortex diatom filter on my 46gal with DE powder and it got clogged/dirty overnight.

What about a diatom filter with Lewatit that was the size of that Ocean Clear canister filter you were selling?
 

scottward

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"I do a large water change in the morning right after the lights come on, then late in the day, there is mad pearling and obviously better growth than any other day of the week.


I've measured plant growth to confirm this also. (stem length and biomass)."


Tom, this made me laugh. Obviously better growth? You notice this growth in the small number of hours between water change and late in the day?


I also find that rocks, wood, plastic pipes etc "pearl" as well. We're you drunk when you wrote this opening post?? :)
 
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Dennis Singh

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Pearling doesn't necessarily mean better growth, just photosynthesizing or over-photo. Just putting it out there...Not directed at anyone. Yes everything pearls after a water change.


Can anyone agree that pearling only deals with lighting intensity? Like you can get poor growth but your plants will pearl depending on light...I believe I've done this, not too sure, memory vague but high light without anything else forgetting to turn on the co2 and such and you still get pearling..
 

UDGags

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With fast growing species I can tell the growth in only a few hours with my setup, which is very similar to Tom's 120. The rotala species (right now I have colorata) will grow very fast. I did a complete new scape 2 weeks ago and I had to trim and replant the the r. colorata 5 days after getting it. I went from 5 to 10 stems roughly 6" length that quickly. You can definitely see a difference with water changes.


Pearling on water change day is different (at least in my mind) than pearling on non-water change day especially if the plant is exposed to air. Tap water is already saturated when we put it in the tank so it's not the plant's saturating the water.
 

Tug

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The only two relevant changes I can think of when using tap water, after the WC the GH/KH might change some but maybe it's just that most are provided with a fairly steady supply of phosphate in the tap.
 

Tug

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Well I'm not necessarily doing anything right - dumb luck likely. It seems there are other tricks to bring on pearling too. But there is a fair amount of visible change in the length of a tall hair grass I have and would like to know the name of. I have also increased my fretz but it's also my CO2 arrived after I turned my tank into soda water. CO2 provides a steady 1.1 degree drop in pH but I'll fixing that soda water look or I'll go mad.
 

Zenzu25

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This is an interesting theory, I have noticed it in the past as well. I wish I would have read this thread a long time ago I would have upped water changes. To think of all those times I skipped out of laziness.
 

Stan510

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Interesting that I always felt that with non Co2 aquariums with a low fish load...the plants did better on less water changes. Say 40% every other week. They kept a better color. The only problem was Crypts HATED the sudden change and would melt some. Even a big 16" container full of them in a 100 gallon aquarium would melt.
With my non Co2 240?..I'm still not sure. Of course the tint that builds up is dropped to near none on weekly 40-50% water changes. But,I also notice that for days Stargrass and Swords lose deep coloring,as I then have to add iron and potassium. But,yes algae can also increase with less water changes.
I should just wait until I see a drop in plant growth and how long that would take,before changing the water weekly as I do now.
Dailey? No way with a big tank. My wife would kill me. Water in Cali is not the cheap commodity it used to be.