Weird spots on glass

[Esquire805]

What is on he back wall

 

[Mastiffsrule]

Hi,

Pics kinda blurry. Not moving and hard to scrape off?

 

[Crustaceon]

Coralline algae. Good stuff, leave it.

 

[Eagle_Steve]

If it’s round and purple, red, or a mix of both, it’s coralline. Sign of a healthy tank and a good thing.

you can scrape off of ya want, but I prefer to leave it. It being there makes other undesirable algae not have a place to grow.

 

[FRAGSNFISH]

Scrape it of and send it to me lol

 

[Esquire805]

Hi,

Pics kinda blurry. Not moving and hard to scrape off?

Yeah its hard

 

[Esquire805]

If it’s round and purple, red, or a mix of both, it’s coralline. Sign of a healthy tank and a good thing.

you can scrape off of ya want, but I prefer to leave it. It being there makes other undesirable algae not have a place to grow.

Some are like dark green

 

[madweazl]

I'd be more inclined to say small tube worms.

 

[vetteguy53081]

coraline algae and if you want to remove (which I do), simply use the edge of an old credit card. Requires elbow grease but comes off, and you don't have to do it all in one day.