Can anyone here ID this algae?

[arminkropp]

Can anyone here ID this algae. actually 3 and your thoughts on the 4th pic. The brown stuff on the middle of the first pic can overrun coraline. I've tried cleaning it off by takeing the rock out of the tank and scraping the rock bare in that spot.

www.mts.net/~kroppa/algae1.jpg

www.mts.net/~kroppa/algae2.jpg

www.mts.net/~kroppa/algae3.jpg


and wondering wht my back wall looks funny with the black spots on the coraline.
www.mts.net/~kroppa/grosscoraline.jpg

TIA for anyone that can help

 

[canyon15]

1. cyano
2. diatom
3. A different color coraline
4.?

Those are my best guesses. HTH.

 

[weemanpow3]

is it purple algae

 

[Devilishturtles]

1. If it's soft I'd say Cyano. If hard, a different color coraline.
2. Agree, diatoms.
3. Agree, coraline.
4. Dunno either. I don't see black spots. I see what looks like purple spots of different coraline but that's it. Maybe a better picture?

HTH

 

[arminkropp]

I've had both Cyano and diatoms before. This doesnt look or feel like either.
I also thought diatoms also need silicates to survive and my tank is at Zero. All water params are perfect other than my pH being a little low.

The stuff on the sand isnt brown, its black in color.
Ans the stuff I was referring to in the forst pic is the brown stuff in the top-middle of the rock. Its very tough. cant take it off other than with a screwdriver or something hard.