white blotches on plants?

[Martin]

i have a friend who is experiencing some kind of weird white spots on his plants.

You can scratch them off, and they kindda feel like sand...


any ideas?

this plant is a Echinodorus uruguayensis

 

[Tom Barr]

Re: white blotches on plants?

Looks like marl, from bicarb use, add more CO2.

If you can rule out the nutrients, simply add enough.

Regards,
Tom Barr