is this algea bad????

TATTOO ya with the lights off I used my LED flashlight I can see a bunch more spots but that's the biggest spot in the pics...

 

And no it doesn't rub off easy... ! used a brush I got from my LFS its hard . doesn't rub off at all actually.

 

probably red coralline if it doesnt come off. Coralline actually comes in a variety of colors, purple is usually just the most recognized. ive had a lot of green grow in my tank

 

Cyano is more like a jelly substance. When I had done, it would disappear when the lights were out. It would come back every day. Coraline isn't jelly like. Coraline I'd more flaky and stuck to the substrate. I found you have to starve out cyano if that's what it is. I just reduced lights and feedings. It was gone after a week or two. But my tank is understocked and over skimmed.

 

Yeah probably coralline, it will back off once it uses the excess nutrients.

 

134 views yet nobody knows what this is ?

 

I think we do know what it is, it's red coralline, nothing to worry about and very attractive!

 

Hahah thanks guys/girls ! Its crazy under my blue leds its kinda glows

 

I would say the dark purple is coralline but the deep red looks like cyano to me. I used to have quite a bit in my FO and it was spongy to the touch and I could pull it right off. If you're saying it is tough to the touch and cannot be pulled off then it's most likely coralline.