Is this detritus?

[ScottyD36]

Hi everyone I have had my tank for about 2 and half months now and this stuff started popping up on the rocks. I just wanted verification that this is in fact detritus algae or possible something else. Thanks in advance.

 

[Webslinger]

start of algae

 

[CoralBlue]

Hi everyone I have had my tank for about 2 and half months now and this stuff started popping up on the rocks. I just wanted verification that this is in fact detritus algae or possible something else. Thanks in advance.

Definitely the start of algae. Also detritus is just the waste left over in the tank you can see (food, poop, crab molts), solid decaying matter. Algae is different and shows your tank is maturing.