LR turning yellow since new light.

[cmonicarl]

I purchased a new led/T5 combo light about 2 weeks ago and one of the lr close to the top has gotten yellow. Could it be that the light is killing the rock. Should I place the light higher? I'm attaching pictures.

 

[Breakthecycle2]

Looks like Diatoms. How old is your tank?

 

[cmonicarl]

I started my tank on march 19.

 

[Ingy]

+1 on diatoms

 

[cmonicarl]

Is this good or bad for my tank and if bad what should I do? Also, what causes it? Its a 15 gal tank.

 

[Ingy]

Silica in the sand and new rocks being consumed by diatom bacteria. It'll go away once the silicates are gone. Normally 1-3 months.