What is this green thing on my light sand substrate?

[newcomer12]

Hey guys,

Just noticed that some spots on the sand substrate from my 10 gal tank has some green spots.
I did some research and it seems to be some algea, but i'm not sure what kind of algea is this and never knew algea grows on substrate as well.
I had my tank light on 12 hours during night before but currently reduced to 6-8 hours. I noticed that that certain area that has green spots receive direct sunlight from my window, so I put a curtain on during day time.

Wonder what is that type of algea and is it harmful and how I can remove it? And if there's anyway I can reduce the direct sunlight to my tank by redirecting it? Having my whole room dark during the day is annoying lol and I don't think moving the tank to different spot is good as well as it's a bit heavy, afraid I might mess it up

Sorry my picture is not too clear because of the tank light and light sand, it looks much greener irl.

 

[StarGirl]

All I see is pink sand. If you think the sand is going to stay that pristine white you will be in for a big surprise later on. No way to stop it. One reason why a lot of people prefer darker substrate. It wont hurt anything. With your shrimp in the tank you will want some algae and build up in there.

 

[newcomer12]

All I see is pink sand. If you think the sand is going to stay that pristine white you will be in for a big surprise later on. No way to stop it. One reason why a lot of people prefer darker substrate. It wont hurt anything. With your shrimp in the tank you will want some algae and build up in there.

hi! yeah the picture looks pretty weird with my top lid light on when i take photo with it. the sand is not pink tho as i just did my weekly cleaning yesterday and the sand got sucked by the syphon looks normal to me. prob just lighting.

here is another person's tank that has similar green spot like mine on sand substrate: https://packaged-media.redd.it/0b8k...=e6754fe75655c9231dd87424d21c2ba7e95a26fc#t=0

 

[Kwikfab]

Turn on a white light, shine it on the sand, and take a picture.

That is, if your camera doesn't have flash.

As mentioned, the tank's light is hiding anything you're trying to show us.

 

[newcomer12]

Turn on a white light, shine it on the sand, and take a picture.

That is, if your camera doesn't have flash.

As mentioned, the tank's light is hiding anything you're trying to show us.

hi. even with my flash on, it still doesn't catch it.

here is a reference link for a tank with similar issue as mine: https://packaged-media.redd.it/0b8k...=e6754fe75655c9231dd87424d21c2ba7e95a26fc#t=0