diatoms or algea

[slimm69er]

this is my first post, but i have been doing alot of reading and learned alot from this site.
my first SW tank 55 gal is this diatom or algea ?

 

[yosemite sam]

It looks like both, there are some diatoms in the first photo (but it doesn't look too bad), and algae in the second. What are your water parameters, and how old is your tank?
FWIW, you should switch out the crushed coral substrate for sand.

 

[beth]

Mostly diatoms.
Welcome to Saltwaterfish.com!

 

[slimm69er]

it is live sand
yes i know the green is algea but was wandering about the brown ?
ph.8.2
amm. 0
trite. 0
trate. 8
spg 1.024
temp. 79
40 lbs. LR
40 lbs. LS
been going about 6 weeks