Recently I posted a question regarding scum on the surface of my tank....no
answers yet but I have new evidence...

I have left it for a whole weekend - when I got back the surface was covered
with a fine green dust. It had bubbles on it which resembled a scum or froth
of sorts. When I dipped my finger in, the scum closed around it, when
retracted there was no evidence that I had distured the surface. It left a
very fine green film on my finger which resembled dust and rubbed off
between my fingers - it looked like powder and not blue-green algae. It's
the sort of scum that you find on stagnant ponds or water that has been left
for an awful long time.

Does anyone know what it is....

I have just put my venturi jet back on and directed it at the surface...
The Chemistry of the tank is fine everything 0 or normal. I do use CO2
injection, I perhaps do not have the amount of plants I would like to have
at the moment. Light is ot too strong 2x20W tritons and 1x30W flora glo.
Filter is Ehein turning over 660lph on a 250l tank.
I have just been rearranging the outlet once again to try and get as much
free floating rubish out as possible.

I do have riccia fluitans on the surface and some ceratophylim demersum -
these have both been removed now as I am thinking on the lines that the
surface plants are producing spores which are then breeding ???

Any suggesstions would be a great help.

Thanks
Martin

If it's similar to what I used to get from time to time, just getting rid of
the Riccia for a while may clear it up. I don't think it has anything to do
with the Riccia, as such, but, in my tanks, it seems to grow explosively in
the sheltered tension film between the crystalwort and the bright lights.

kush

"You can't have everything - where would you put it?"

LeighMo wrote in message
...
I get this sometimes. I think it's a floating algae, sort of like green
water,
but only at the surface of the water. Like most algaes, the key to
controlling
it is nutrient balance. Last time I got it, I think it was because I let
nitrate drop to zero.

If you get your nutrients in balance, it goes away, though it might take
awhile. In the meantime, surface turbulence will help break it up. You
can
also skim it out with a jar, the way you'd remove fat from gravy.


Leigh

http://www.fortunecity.com/lavender/halloween/881/

Sometime back Tom responded to my posting here it is

##########################
The Green dust on my glass is rally a pain. I would appreciate any help in
this regard.

Thanks and Regards
Dominic

Green dust is a zoospore that after you wipe it off, it simply re
settles back on the glass. They look like little spikey hemispheres.

A good way to get rid of it is to do a good scrubbing of the glass
etc, do a large water change right afterwards, and-or run a micron
filter or some extra floss etc to remove the spores before they re
settle back and start growing again.
The filter byitself can do a good job if you scrub a couple of times a
day.

They re settle in about 1-2 hours time and you have a new film
growing.

It's not particularlly harmful to mplants and seldom grows on them.
But it can be annoying since it coveres the glass fast. Some Pleco's
will eat it etc.
Regards,
Tom Brr
##########################
--
Thank You

Dominic
http://www.dlink.org/aqua

Well thanks to everyone for their response.....All your replies seem to
describe it well. I actually get rid of it by putting a paper kitchen towel
into my large net and swirling it around the surface - it kinda works!!!

I have actually removed the Ceratophylum and Riccia now - for a whole day
and it doesn't seem to have returned yet....However..we will see. I have
scrubbed the glass - though there was not much algae on that anyway - Ottos
Rule OK....

I will be taking further measures like a big water change this weekend and I
will be putting in more plants...

One outstanding problem is the Nitrate - it is 0 as is everything else -
what there is is taken immediately by the plants even though they are
planted in Flourite which should be supplying the nutrients.

Should I start supplementing with liqued Plant food ????

Thanks again

Martin