Algae and Peat filtration

Just when I thought I had brush algae under control, my 6-week old 90gal 
plant tank appears to be invaded by a different type of algae. This stuff 
grows really fast, has long (1-2 inch or longer) branching strands grown 
from a single point, and is dark green in colour. I can remove it 
manually when it grows over 1 " long, but it always comes back the very 
next day. It's mostly on the leaves, although a few are now growing on 
the filter tubes. Is this another type of red algae, beard algae perhaps?

The proliferation of this "new" algae coincided with my adding of peat to 
the Fluval filter. I read in one of the plant books that red algae 
prefers harder water with a high ph, and recommended using peat filtered 
water for the first two months of a new tank. My concern is the peat may 
have increased the amount of nitrate and or phosphate in the water, 
causing an increase of algae growth. However, according to my cheapo test 
kit, my Ammonia is zero, Nitrite is zero, and Nitrate is also zero. I've 
been changing 30% water every week. 

My water is relatively hard, even with peat filtration, it is 130ppm Total
Hardness, 120ppm Alkalinity, and pH is around 7.6 with 2 bottles of the
yeast thing going. I don't have a fancy co2 reactor - just a couple of
airstones. Dunno if that's the cause, or if my water has too high of a
buffering capacity, but the co2 thing only drops the pH from 7.8 out of
the tap to 7.6 in my tank. The yeast bottles are also not that consistent
in terms of producing co2 bubbles. I bought a 15lbs co2 tank today and
will get a needle valve tomorrow and try a bit more reliable manual co2
injection to see if that's going to lower the pH down to about 7, and 
whether that has a positive effect on the algae.

Ironically, all my plants, with the exception of the Jungle Vals, are
doing quite well. It's just that the tank looks awful with all the algae
growing on everything. My final hope is that when I go to visit my sister
in PA next week, I will bring back 10 SAEs (from either Ned's or Albany
Aquarium) and hope that would help with the problem. 

If all fails, I think I will turn the tank into an African Cichlid 
community (do you sense the despair in another newbie dropout-to-be :-(?)

 John Y. Ching (jyching at watnow_uwaterloo.ca)    |
 Pattern Analysis and Machine Intelligence Lab	| 
 Department of Systems Design Engineering      	| 
 University of Waterloo, Canada            	|