Algae in Aquarium
Q: I have a 20g long (30" x 12" x 12") with a standard flourescent light over
it, all my water test results are excellent (0 amm., 0 nitrite, 10 nitrate,
pH 6.6) and I'm still having trouble with my plants. My dwarf and narrow
leaf sag got a black "fuzzy" mold on them. Another site suggested
a 3 day black out then remove any leaves with the fuzz still on them,
which I did. my plants still look awful and the black fuzz is coming back.
The black fuzz is the "black beard algae", probably
one of the most common algae types present in planted aquaria.
It appears in condition of low nitrates and excessive phosphates.
The blackout, recommended by the other site, is a good measure indeed.
You can try to turn off the lights during the day for a couple hours too
(e.g., 7-12 lights on, 12-2 lights off, 2-7 lights on). Such a break
in the light presence affects the algae's ability to photosynthesize
and stunts its development and growth.
The most common method of controlling this type of algae is
introducing the siamese algae eater fish - this is the only
fish known to feed off this algae.
Another way would be to artificially increase nitrate
concentration by adding potassium nitrate into the tank.
You can read a little more details on this and other types
of algae here:
Q: I cant seem to find any simease algae eaters locally,
should I turn off some of my lighting for the time being?
The answer is yes, it would be beneficial to turn
some of the lights off.
Also, turning all lights off for an hour
or two during the day time would
help too: such a disruption in the
light time would cause interruption
in algae's photosynthesis while not
harming the plants.
Another way of fighting the black
beard algae is to use phosphate removal:
All these methods may take about a
month to reach reasonable results.
Also, it is recommended to remove
infected plants from the tank
after the treatment is over and
the algae does not grow any more.
Q: Do you have any suggestions for the brown algae?
Brown algae usually happens due to excess of lights.
If possible, you would need to reduce the daytime
of your lights at least to 12 hours, 10 - even better. If it's not possible
try to turn lights off for a couple of hours during the day
(e.g., 6-12 lights on, 12-2 lights off, 2-10 lights on).
Also, otocinclus affinis are very fond of this particular type of algae.
This algae frequently happens in new tanks, it tends to go away
after the environment stabilizes.