Substrate is getting white

[Federal]

Hi friend,
Since a week I have noticed a substrate is getting white. Initially there are appeared a small areas, after little time they is getting bigger.
If someone has any idea what to do? Don't want to make rescape.
Thanks!

 

[_Maq_]

Probably calcium carbonate. Harmless. You water is hard, I suppose?

 

[Hufsa]

If this tank didn't have water in it I would say mold 🤔
How long has the tank been running? Is the flow over the substrate strong? Any white around the plants?

 

[Hanuman]

Hi friend,
Since a week I have noticed a substrate is getting white. Initially there are appeared a small areas, after little time they is getting bigger.
If someone has any idea what to do? Don't want to make rescape.
Thanks!

Looks to me this is a new scape. If so, the soil is not becoming white but showing it's actual color. The light is also making it appear whiter. The darker parts of the substrate are probably covers with diatoms making them look darker. Eventually all diatoms will disapear and the soil color will be homogeneous. This has happened to all tanks I have setup.