[piercho]

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Lobophora (as mentioned above). Forms brown circular encrusting tiers and fan-shaped fronds; exhibits many colors and morphological variations. The underside of the fronds (leaves) have felt-like surface, the top side is smooth.

Psuedolithoderma (=Ralfsia). Forms brown, tightly adherent circular crusts on rock an glass.

Neither is palatable to most herbivorous fish. Possible herbivores are Diadema urchins and Naso tangs. Best removal strategy is hand removal. [Sprung, 2002] [Huisma, Abbott, Smith; 2007]

Also brown, encrusting, and forming fan-shaped blades: Distromium, which is thin and uncalcified. Padina, which is calcified.

An extreme but effective startegy for macro algae erradication is to remove the rock, wire-brush off the algae, rinse the fragments away, and then spread a paste of lime (kalk) where the algae was. Wait a few minutes and rinse away the lime paste. Most anything smothered by lime paste is likely to be killed (pH of 12). Trying to use lime paste in the tank is likely to spike pH in the tank. Trying to scrub off the algae in the tank is likely to spread the algae by the loose fragments. Expect the rock to appear bleached where the paste was used. For algae that spreads readily by spores (ex: bubble algae like Ventricaria or Valonia) this is unlikely to erradicate the algae as unseen "babies" are probably already growing throughout the system.