Red/Marron algae is growing on sides?

[TCoach]

I did a ~40% water change today (First one in several months) to work on correcting my parameters. Anyway, when I did, I noticed my 2 corner sides are covered with a reddish/maroon/purple algae coating. As you can see in the pictures, it covers everywhere except where the powerheads were.

Any idea what it is? It is not coralline algae ( I have some on my overflow).

Also, any idea what all the white dots are?

 

[NowGlazeIT]

Is the algae a bit slimy and comes off when you rub it? If so I think it might be a type of dinos.
the white spots look like spirorbis

 

[TCoach]

Is the algae a bit slimy and comes off when you rub it? If so I think it might be a type of dinos.
the white spots look like spirorbis

Comes off if I drag my nail across it. It’s not super loose.

This is a 17 year old thank that I adopted late Spring. It has real live rock (prob Fiji). I’m not worried about it, just curious.

Thanks!