My beautiful (at least to me) open-topped tank has developed a serious surface scum problem. This is the weird, semi-solid, whitish stuff that others seem to fight from time to time. The scum builds up in just hours, and when I skim it manually with a cup, it breaks up into stringy nasty bits in the cup.I hate it, and am afraid it is inhibiting gas exchange enough to cause more than just aesthetic problems.
There seem to be two schools of thought on this: (1) white scum is a symptom of bad water quality, or (2) it's a normal byproduct of happy biological activity, so agitate more or skim it.
I'd love to believe it's #1, but I'm flummoxed as to what could be the problem. This is a heavily planted 57g tank, pressurized CO2, aquasoil, eheim 2028, and a modest bioload (a half-dozen otos, 15 small rasboras, and a bunch of amanos). I don't overfeed, and I have a Koralia nano agitating the surface. Terrible scum. By contrast, my "upstairs" 20g has no scum. The 20g also gets pressurized CO2, but it uses eco-complete instead of aquasoil, and has no driftwood. (The downstairs tank has tons.)
So now I'm looking for mechanical options for getting rid of this stuff. I can't just use a surface skimmer attachment for my Eheim--the filter is plumbed through the tank bottom and I can't/won't run a tube all the way to the surface to reach a skimmer.
I'd like to create a tiny standalone skimmer that pulls water from the surface and sends it into the main water column of the tank. It doesn't need to "filter" the scum, just chop it up and send it into the water column.
Anyone have any ideas or experience with this? I've seen a description of a modified duetto
, and I'm also wondering if I could hook up an off-the-shelf skimmer attachment
to a small submersible powerhead. Or maybe just invert a hagen elite?