Identification help appreciated.

[druid1200]

This red and orange substance just popped up in my 265 this week. My Nitrates are high and I recently did a 25% water change so I'm wondering if it's some type of Cyano? Should I eliminate it? Thanks

 

[Squishie89]

If it blows off easily it is probably cyano or some form of cyano. If it is hard and does not come off it might be coraline.