Chemistry

Richard Harker continues this topic in Part 2:

Close-up of carbons tested in this two-part series. Clockwise from upper left-hand corner: Carbon from Lifegard, Hydrocarbon 2, carbon from ESV and carbon from Seachem.

Cyanobacteria is a type of bacteria that can bloom, and then blankets the sand and rockwork in our tanks.  It's an eyesore and people object to its presence in our systems.  You have a few products to help combat it, and then there is the non-chemical approach as well (explained in the article linked below).

RedCyano Rx (by Blue Life USA) works well.