Re: Rift Lake Cichlids and Red Algae

Liisa's comment about African cichlids reminds me of an interesting
observation I made when I was 'raising' a lot of red algae 10 years ago. At
that time I was maintaining a few heavily planted aquaria with neotropical
cichlids and many other tanks with breeding Tanganyikan cichlids.  The plant
tanks had lots of red algae. There was ample opportunity for the red algae
to infest the cichlid tanks, but they never seem to get any!

All of the African tanks had a thin substrate composed of crushed coral
which buffered the water and kept the pH around 7.5-7.8. I did not add any
other chemicals or 'African Cichlid' salts.   Each of these tanks had some
java fern and java moss. They also received less lighting - a single strip
light (In the neotropical tanks, the pH was neutral to acidic as I recall
and the KH was very low. The lighting was brighter, 2 bulbs).  At the time I
attributed the lack of red algae to the difference in pH, carbonate hardness
correspondingly lower CO2.

Although these tanks did not have the tufts of red algae seen in the 'plant'
tanks, they did have their rocks covered with small unraised black dots of
algae.  As best I can recall, these dots look like the spots in my current
'test' tank with red algae in which I put a half dozen SAE a few years ago.
The tufts of red algae quickly disappeared in the SAE tank, but the dots
remain where the algae once grew.
Now I wonder if the Tanganyikan cichlids, including the fry could have been
eating the algae! Does anyone have similar observations regarding Rift Lake
Cichlids and red algae?