# Red spot algae?



## Tshavo (Sep 1, 2014)

Looks like coralline algae to me.


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## Grumpy1415 (Oct 15, 2013)

Red (brush) algae maybe. Do you have high pH or high kH?


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## werebug (Nov 20, 2014)

It's not in my tank, but I will ask the owner tomorrow. Are saltwater algae known to tolerate freshwater conditions? A SW alga was my first thought also, as I've never encountered any rhodophytes other than black brush in FW aquaria. This matches neither the color, growth pattern, or preferred location of black brush algae outbreaks I've seen.


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## Kathyy (Feb 22, 2010)

Look up Hildenbrandia, couple species there. They aren't supposed to be coralline though. Possibly hard to scrape anyway? A video.http://youtu.be/yLKCevEl0Hc

BBA is a red algae as is staghorn. Both turn pink as they die. http://en.wikipedia.org/wiki/Audouinella http://www.aquascapingworld.com/algaepedia/full_view_algae.php?item_id=80 http://en.wikipedia.org/wiki/Compsopogon


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## werebug (Nov 20, 2014)

Thanks Kathyy, this definitely seems to match descriptions and photos of Hildenbrandia. Fun fact from the Wiki page:

_The presence of H. rivularis near Stonehenge has been put forward as a reason for the site's perceived mystical properties. Flint in pools near the henge takes on a pink hue a couple of hours after being taken out of water due to the presence of the algae. It is assumed that ancient hunter-gatherers would have seen the rocks as having magical properties and would have deemed the site worthy of interest._

How cool! We're psyched to have an ID, and I think my boss is going to keep it, for science!


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