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Red root floater (Phyllanthus fluitans) and the effect of nitrogen (N).

dw1305

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Hi all,
Earlier in the year (May 2024) @simon_the_plant_nerd and @megwattscreative kindly supplied me with some Phyllanthus fluitans (Red root Floater) to experiment with and this is what happened.

Cheers Darrel
 

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Hi all,
What was the experiment?
Good question, I'm getting to that. The reasons was that I wondered if it might offer an <"extension to the Duckweed Index">.
  • <"VIMI"> and the <"2 hour aquarist"> have been experimenting with the leaf colour in "Red root floater (RRF)" and whether you can make <"the plants redder"> with nitrogen (N) limitation.
I've never had <"much success with Phyllanthus fluitans">, and it has never persisted with me. @Hanuman had some input where he had grown Phyllanthus successfully under high nutrient levels.
......... My pond outside has exactly these two. Phyllanthus is a weed. The whole surface of the water is usually covered in a matter of a week. I need to scoop them weekly else they simply block all light. On the other hand, the Limnobium seems to grow slower at least in terms of multiplication .........
In this case the plant was lush, but green.

I think I now know the reason for my failure with RRF, and that is because I've grown it much too lean and it isn't happy with <"petrol fumes">.

This one has received @Happi 's <"solufeed mix"> and also some extra nutrients, because the low tech nutrient doser 😉 (the cat) has malfunctioned and keeps drinking the water after she has eaten her food. The bowl is topped up with tank water and gets a 100% tank water water change every couple of weeks.

Healthy_Phyllanthus.jpg


Everything healthy and green and the RRF with a distinct reddish tinge.

cheers Darrel
 
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Hi all,
This is in the tank, the same fertiliser mix, but a lower dosing, and no extra nutrients.

Not_so_Healthy_Phyllanthus.jpg

Using the Duckweed Index the Amazon Frogbit (Limnobium laevigatum) is still fine, but the RRF really isn't enjoying itself.

cheers Darrel
 
Hi Darrel and other members,

the strong reds are also achieved with strong lightning, especially the one that is rich in the blue spectrum with small amount of UV in it.
1720279801857.png


N limitation also helps with the coloration. extra Fe has very little to do with the intense coloration of the plants and isn't required to be dosed at high level.

We talked about how UV was almost always missing from the LED and Experiment was conduced by one of my friend few years back:
1720280447911.png
 
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I have a tank where I dose APT3 and tank where I dose EI. I can say that my rotala blood red almost the same color in both tanks.From my experience the good coloration is about strong light, N limitation plays a very lottle role
 
So I tried RRFs because i am sucker for anything red in my scapes and in my tank without dosing N they stay green and kept multiplying so I got feed up and left them out in a bucket with old tank water in our 1 week of British summer they have turned red , will post some pictures tomorrow, in my tank though I think my tap water has lots of nitrates and they keep getting the nitrates and outside they have used up all the nitrates plus the UV from sun turned them red.

I think my tanks are high light both have chihiros wrgb slim and 2 run for 8 hours @ 70%.
17203384028764342437595734480512.jpg
 
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RRF needs full sunlight to turn red. Even half day filtered sunlight in my west facing window is not enough. After I placed mine outdoor in summer, it turned blood red.
 
I have a tank where I dose APT3 and tank where I dose EI. I can say that my rotala blood red almost the same color in both tanks.From my experience the good coloration is about strong light, N limitation plays a very lottle role
I think the tank were you are dosing APT3 is not so much N limited as you think then because N limitation will inevitably induce a deeper red coloration OR, the tank where you are dosing EI is low in N for some reason. Rotala blood red will actually color up easily without much N limitation anyway. The difference will be subtile with more of a red/orangy color under higher N and more of a deeper red under N limitation.

RRF needs full sunlight to turn red. Even half day filtered sunlight in my west facing window is not enough. After I placed mine outdoor in summer, it turned blood red.
No it does not require per say full sunlight. N limitation will achieve that perfectly fine. You do need some light obviously since that is what drives plant growth and metabolism but full sunlight is not required to turn them red. In your case the full sun light increased the plant nutrirent requirements/intake and growth speed probably ending up inducing an N limitation in the water column.

I can induce red coloration in these plants in low/medium light but it will take much longer as plant growth and metabolism is significantly reduced.

 
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Is it possible that there are different variations of this plant? I have it in all my tanks and it grows well, but they've never had any hint of red. A while ago I added it to my blackwater tank with zero fertilization and some of the plants stay directly under the light, but still no red in them at all. Considering how little water I change and how the surface is entirely covered with plants, I doubt that there is much nitrogen in the water.
 
Well, last 6 weeks I’ve been trying out the ‘floater index’ with frogbit and RRF myself, both doing great. IMG_2816.jpegIt seems to me RRF doesn’t do well in decent surface water flow.

I’m no fan of leaning anything nutrient wise. Front loading 20 ppm NO3 in my tank gives RRF no hint of red at all.

Goal is to front load the rest of the elements at least 150% higher than N (plant composition ratio wise) and to change water when RRF is showing reds.
 
I think the lighting intensity does have a significant impact on the RRF demand for nitrogen. Below you can see RRF grown in the same tank. Only difference is the red ones are in my duckweed index container which has access to a lot of light and the green ones are in the tank in a dimmer area.
20240712_111752.jpg
 
I think the lighting intensity does have a significant impact on the RRF demand for nitrogen.
That’s virtually the case for all plants.

Below you can see RRF grown in the same tank. Only difference is the red ones are in my duckweed index container
Not sure I undertsand here. Are they in the same tank or in a separate container?

In any case the redness of this plant if a function of how much N there is available. One can have RRF at full sunlight and it could still remain mostly green if the water is supplied with enough N. The only place where I see this plant turn this deep red is in tanks where N is basically close to, or at 0 with no water movement (or very minimal).
 
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Not sure I undertsand here. Are they in the same tank or in a separte container?
The duckweed index container has water flow connected to it from the display. They're both in the same water just different distances from the light.
20240702_161335.jpg
 
Lovely to see a view of the equipment @RickyV! It provides a good sense of what goes on behind the scenes in very large aquariums.
 
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