marcus wrote:
I am with Win. my rocks have gone green too, not much you can do except take the out the water and light. I don't know why its gone brown rather than green? may be iron in the rock? is it algae for sure?
Hey Marcus,
Here is some info on this that I thought was interesting. There is some very plausible theories as to why this algae often appears in newly set up tanks and then later disappears. If the silicate (Si) to phophate (P) ratio is high, then "diatoms" are likelyh to have a growth advantage over true algae types and Cyanobacteria. Some of the silicate may come from the tapwater, but it will also be leached from the glass of new aquaria, and potentially from silica sand/gravel substrates to some extent. Later, when this leaching has slowed, and phosphate is accumulating in the maturing tank, the Si:P ratio will change in favour of phosphate, which is likely to favour the growth of GREEN algae instead.
I also found that limiting light will not deter this algae, as it can grow at low levels and will normally out-compete green algae under these conditions.
So maybe this stuff will disappear, I believe it has to do with silicates in my tap water. Not everyone has a problem with this golden/brown algae and silicates. I am just seeing what it will do. Doing a water change today and cleaning up some.
