All it takes is one tiny cell to create a forest of red slime. Phosphate, nitrate, and other dissolved organic compounds are the most common cause of red slime. Although safe in lower concentrations, high nitrate levels can cause severe disease in fish, let alone cause an increase in algae growth.

In general, cyano or cyanobacteria is red colored and can be stringy or a slime that coats surfaces.

Cut Down on Your Lighting Don’t run your lights more than 7-9 hour a day. Too much light leads to explosive cyanobacteria growth. If you do not have corals, you can also “blackout” the tank for 3-4 days. Keeping the light off for extended periods of time can get rid of red slime algae once and for all.

While cyanobacteria in aquariums does not usually harm fish, it can potentially kill your plants if their leaves are covered and can no longer photosynthesize light. Another way to identify blue-green algae is by its distinct odor.

Too Much Reef Food – Overstocking / overfeeding, your aquarium with nutrients is often the culprit of a cyano bloom. Regular water changes dilute nutrients that feed cyanobacteria and keeps your tank beautifully clear.

Reef Safe Hermit Crabs Dwarf Blue Leg Hermit Crab (Clibanarius tricolor) grows to a size of about 1 inch as it eats all kinds of algae, including red slime algae. Dwarf Red Tip Hermit Crab (Clibanarius sp.) eats many kinds of algae, including red slime algae (cyanobacteria) and sifts the sand.

Beat Cyano in five steps

1. Syphon off and remove.
2. Change water.
3. Increase mechanical filtration.
4. Increase flow.
5. Add beneficial bacteria.

UV destroys organics, as does ozone. Both will help break down nutrients in the water, thus slowing the growth of cyano.

Chemical treatment is the most common treatment method, and also the most damaging to the environment. It involves using copper sulfate and hydrogen peroxide, which cause sudden death or lysis of cyanobacterial cells. Massive amounts of cyanotoxins are being released back into the water.

Cyanobacteria, formerly called blue-green algae, are not really algae but are a phylum of photosynthetic bacteria that live in moist soils and water. The species’ structures can be unicellular to filamentous and some species are colonial. It can grow quickly and can cover the substrate in the aquarium. When disturbed, it comes off in sheets.

This is a tank with a severe cyanobacteria problem. Conditions like this can be seen in as little as four days from the initial sighting. It looks as though the fish have been redecorating again, draping sheets of thin green algae over every surface and even hanging it from the sides of the tank for good measure.

Unlike brown algae, cyanobacteria are not eaten by plecostomus and other algae eating fish. So, do not count on these fish to help clean up your blue-green algae problem. As with any algae, keeping the aquarium clean and performing regular water changes are the best preventative measures.

The cyanobacteria are very hard to kill, because it is a very primitive form of life, which can survive in very harsh environments. Cyanobacteria is very easy to detect in aquariums. Blue green algae has a dark green color, it is very slimy, it grows and spreads over any surfaces and has a specific bad smell.