Alllgaee!

[K.J.]

I noticed one of my java ferns today. It has a thin, dusty, patchy coat of algae - slimy to touch and brown. What is this and will it spread?

 

[JamesC]

Sounds like diatoms. Look at my website as I have some photos for identification. Normal in new tank setups and usually goes in a few weeks. Also can be caused by low light levels. More details of setup would help.

 

[K.J.]

Yup, that's it. Setup:

Tank: 10 US Gallons
Plant affected: Java fern
Other plants: Vallisneria, Water Wisteria, & hornwort
Lighting: 50 watts
Cleaning: Haven't figured that out, I would say 20% weekly, the tank was just set up.

 

[JamesC]

A newly setup tank is why then. Silicates in the gravel are the cause of the diatoms. Keep up with the water changes and cleaning, and the diatoms should soon go.