Pebbles - Yellow Stain

[robmol]

Ive got this yellow stain on my pebbles, i havnt changed anything and it has been fine untill now. Only thing i can think of is some new food i got my clown loaches which are a browny yellow colour? But surely this wouldnt stain the pebbles?

Any ideas?

Cheers

 

[tom_os]

sounds like algae

take one out a give it a scrub, see if it comes off