Diatoms vs cyano

[Psychojam]

Simple question, how can you tell the difference between diatoms and cyanobacteria?

I have a brown slimy covering in a 5 week old tank.

 

[seapug]

Probably diatoms but it can be hard to tell the difference. Both are common in relatively young tanks so no matter what it is, it will go away with time.

 

[kkyyllee]

cyano is slimy, sounds like you have cyano

 

[volk23]

no, it is cyano, seems pretty red to me, diatom is brown

 

[kevin2000]

S/B a zillion pictures of both on the web .. worth a search.

In general .. diatoms are the first to show up as a problem algae in the tank .. often a brownish carpet of algae.

If your tanks cycled then a few snails will make short work of a diatom outbreak ... if the snails don't touch it then chances are you have cyano. Lots of cyano threads with solutions posted every week.