Miles;2054466; said:ammonia burn is red sores on the underside of the disc..
these symptoms are usually from very poor substrate maintenance..
I've seen ammonia burn similar to that on one of my rays that was imported on top of the disk but not that bad. It didn't show up the first day but a day later it was worse and two days later even worse. It then began to heal after.
It does look like fin rot but would need alot more time to look like that.

