smelly-green-carpet like algea

["Yvan Alleau" <yalleau at coas_oregonstate.edu>]

Hello everybody,
I have been looking in the lst of previous e-mail to find something related
to my issue but did not find anything. However, i am pretty sure that this
type of algea problem has been encountered by some of you and therefore
surely already discussed.
For the last 18 years that i have been keeping and breeding fish I've never
experienced myself the algea problem i have now.
The algea  looks like a dark green carpet and covers everything from plants,
glass to sand. When you touch it and bring it out of the water it has a
strong smell. Nothing appeares to eat on them (shrimps, catfish...). My
guess from its smell is that it might be  toxic if swallowed (but maybe
not).The algea is even growing in the filter !
For now, i have only tried to get red of it when cleaning the tank but it
comes back quite fast.
Therefore i need your help to:
1) understand what are the conditions for the algea to appear and grow
2) find a way to eradicate the algea
The tank is a display tank containing: heckel and alenquer wild discus,
various varieties of apistogramma, corydoras sterbai, hypancistrus zebra,
tetra cardinals, caridina japonica, otocinclus. plant species include: java
moss, anubia barteri and nana, nomaphila stricta, tiger lotus, echinodorus
amazon.
Temp = 26-27 deg Celcius  (78-80 F)
pH = 6.9
conductivity = 170 uS
filter is magnum 350 containing lava rocks and white coton type of filter
(don't know the general name for it).
Watter changes are done ones a week (20%) except when discus fry are
present.

I would appreciate any suggestions.
thank you very much


Yvan Alleau
712 NW Kings Blvd
Corvallis, OR 97330
College of Oceanic and Atmospheric Sciences
Oregon State University
office (Burt 222): 737-3649, to be used wisely!
home: 738-0606

PLEASE NOTE NEW E-MAIL ADDRESS:
yalleau at coas_oregonstate.edu

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