Giant duckweed - Spirodella polyrhyza

[andusbeckus]

I’m looking for a floating plant and came across a large version but can’t find any for sale?
Has anyone had any or have any more info on it?

 

[dw1305]

Hi all,

Has anyone had any or have any more info on it?

It likes hard water with high conductivity and nutrients. I might still have a little left, but I don't have any suitable tanks for it.

cheers Darrel

 

[andusbeckus]

Hi all, It likes hard water with high conductivity and nutrients. I might still have a little left, but I don't have any suitable tanks for it.

cheers Darrel

Where did you get it from originally? It’s strange I can’t find any at all online in the uk.

 

[dw1305]

Hi all,

Where did you get it from originally?

PYO unfortunately. They were plants that I picked up when I was on field work. I'll see if I can perk up the bit I've still got.

It came from one of the <"ponds in Bristol">, which I surveyed in the summer. The last place I saw it before that was at the <"Steart Marshes project">. It was really common there in some of the rhynes, which are freshwater but high conductivity and nutrient status. It isn't a very common plant.

cheers Darrel

 

[andusbeckus]

Thanks Darrel very much appreciated

 

[mort]

Is this the only species with the red underside here in the uk? If it is we have it here in the broads. I had some in my pond but it dissappeared after growing strongly for a short while.

If you can't get any then bump this when the weather warms up and I'll see if I can find some for you.

 

[dw1305]

Hi all,

Is this the only species with the red underside here in the uk?

Yes, red undersides and more than one root from each individual frond.



All the Lemna spp. have one root per frond, and Wolffia doesn't have any roots.

cheers Darrel

 

[dw1305]

Hi all,

I might still have a little left,

I found a little bit in one of the tanks today. I'll put it under the light in water with a lot more hardness and nutrients and see if I can bulk it up.

cheers Darrel

 

[andusbeckus]

Slightly different subject but do floating plants help with biofilm at all? Especially fast growers like duckweed.

 

[Parablennius]

I keep Frogbit and Ceratopteris as floaters and I've found that when they get too dense they actually "retain" surface bio-film. Normally my surface water skims off over a weir into the filter but dense growth can prevent this. HTH.
Cheers