Newly Cycled Tank with Brown Algae!!

[Tomspot]

Hi,
   Have just completed 21/2wk. Cycle of 120gal.
NH3 0,NO2 0,NO3 2,GH 160,KH 240,PH 8.2
Am looking to stock with Tanganyikans.
Before this happens I have to clear tank of Brown Filamentous Algae.
It's spread on Rocks and White Sand substrate, with some patches on plant leaves.
It's semi-planted tank with Lacerock.
Lighting on for 8hrs/day 2x65w 6500k
2xXP3 Rena Filters and 2x300w Heaters.
Substrate is Silica sand, Crushed coral/Gravel and Flourite.
Thought of Blacking off Tank for a few days, but this may harm plants.
Is there an additive I could use that will not harm plants.
HELP!!!!
          Geoff

[markw]

Brown algae is pretty common with a new tank. Especially at this time of year with water effected by spring runoff. Sometimes even tiny amounts of phosphates will generate the algae. Usually it disappears on its own after a few weeks with fish adding to the biological cycle. The algae has to compete with the bacteria for nutrients and the increased load will starve out the algae. If you want to accelerate the removal, try some AB plecos. They'll tolerate the higher ph and hardness of a Tang. tank and will eat the algae.

[Tomspot]

Thank's again Mark,
                          Was wondering about Phosphates myself. This being about the only constituant of my tap water(from a well) I didn't check.
Tonight will do a clean up & Water Change.
Will see how well this works before I go messing with any additives.
As soon as possible will take your advice and add some fish.
In the meantime will continue adding around 2-3ppm of NH3 to keep Bacteria fed.
Thanks again,
                  Geoff