Substrate

[Ozzy Ozborne]

I have noticed small amounts of green algae on the sand substrate in my tank.Over the past few weeks it seems to have crystalised and feels course when picked out.
Any idea what is causing this and what should I do?

Thanks

 

[Ozzy Ozborne]

Anybody got any ideas ?

thanks

 

[ShoC]

are you able to take a picture?

doing so will probably result in knowing what it is instantly