# lighting distance for frogbit?



## 1uke (12 Oct 2009)

Wanted to try grow some Frogbit but my T5s/T8s are mounted directly on the tank about 3 inchs from the water. Would this just burn the frogbit?


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## 1uke (13 Oct 2009)

Have aquired some I think, So might aswell test.


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## 1uke (13 Oct 2009)

Anyone with Amazon Frogbit tell me how far there lights are away from water surface?


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## chilled84 (13 Oct 2009)

My lights are 2 inch from my frogbit im giveing you. They thrive so well. There growth also depends on whats under the leafs too. Some people loose the tenticals, I did at first but now there takeing right off.


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## the fife flyer (21 Dec 2009)

Hi,

I have a Rena Aqualife so the distance would be about the same as yours, running 4 x 5ft T8s so it gets a bit warm under there. My frogbit is growing well.

One question though. Should the roots have "hairs" growing from them?


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## 1uke (21 Dec 2009)

Hey, The frogbit has been thriving in my tank since I added it and 3 times now have had to chuck loads. My frogbit had hairs on the roots until I added Siamese Algae Eaters and that's one of the first things they cleaned so I'm assuming its algae as there's no hairs on the roots nowadays.


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## aaronnorth (21 Dec 2009)

Mine are about 6", but i also have a perspex cover


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## the fife flyer (21 Dec 2009)

Hmmmmm interesting.

The hairs are in a sort of uniformed growth and assumed they were meant to be there.


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## 1uke (21 Dec 2009)

Just looked at mine again and yes there are tiny little hairs on them. I think they stood out more before because they had tons of stuff stuck in them.


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## Kevina (22 Dec 2009)

Hi, The hairs are part of the plant, the hairs are what they use to extract vital nutrients from the water. any fish that likes vegatable matter will certainly eat these hairs away as SAE's did on mine. The plants will live after hairs have been eaten but will not thrive to their true potential.


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## dw1305 (22 Dec 2009)

Hi all,
They will take as much light as you can find, any damage is likely to be heat related. Yes definitely root hairs, for the reason mentioned, something that was well known, but only demonstrated scientifically relatively recently actually using _Limnobium_:
Gilroy, S. & Jones, D. (2000)
"Through form to function: root hair development and nutrient uptake "
_Trends in Plant Science_ *5*:2 pp 56-60 


> Abstract:
> Root hairs project from the surface of the root to aid nutrient and water uptake and to anchor the plant in the soil. Their formation involves the precise control of cell fate and localized cell growth. We are now beginning to unravel the complexities of the molecular interactions that underlie this developmental regulation. In addition, after years of speculation, nutrient transport by root hairs has been demonstrated clearly at the physiological and molecular level, with evidence for root hairs being intense sites of H+-ATPase activity and involved in the uptake of Ca2+, K+, NH4+, NO3âˆ’, Mn2+, Zn2+, Clâˆ’ and H2PO4âˆ’.


 Here's their "Limnobium" root hair figure:




We have used _Lemna_ in the past to measure their response to the level of nutrients in the water column (from the "The Charms of Duckweed" http://www.mobot.org/jwcross/duckweed/duckweed.htm,  but I've found that both Nile Cabbage (_Pistia_) and Amazon Frogbit (_Limnobium_) shows a similar, but much more impressive, response to the level of nutrients in the water column, with low nutrient levels producing relatively smaller leaf rosettes, but fantastic large and "frilly" roots.

cheers Darrel


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## the fife flyer (22 Dec 2009)

Ah well.....it seems mines are lacking in nutrients as the the roots are very hairy.

Apologies to the OP for hi-jacking the thread.


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