Huh? Did Hornwort Clear my Surface Scum Problem?

pat w

Nov 4, 2009
Daphne, AL (east Mobile Bay)
As some of you know, I've been at war with Rhizo of late. It's under control now, I believe, but I also had a pretty noticable surface scum problem, too. My attention was focused on the Rhizo so I did very little to address the SS except try to increase surface agitation via redirecting the flow of my filter spray bars. That wasn't getting me anywhere and I was about to order a surface skimmer to attach to one of my filters. In the meantime I bought some Ceratophylum demersum (Hornwort) and anchored it to the spray bars to keep it from floating all over the tank. The purchase was just to increase biomass in the tank. Within a few days the surface scum had been reduced to little more than a thin broken film and now it appears to be completely gone.

What's up?



Lifetime Charter Member
Lifetime Member
Jun 21, 2009
Surprise, AZ
Who Callin' Scum?

Hi Pat,

It is possible the Ceratophylum demersum is helping clear the “surface scum,” Hornwort grows quickly that should help the system. :)

The “surface scum” is bio-film. Bio-films are “secondary colonizers” while most of us tend to think of microbial life in our aquariums as planktonic, in fact the vast majority (98% +) are contained within the slime that inhabit pretty much every surface. :eek:

I suspect that as your system is maturing the nature of the microbes that make up the “scum” are changing and redistributing. :cool: