Protein "sludge" on surface of water

[argnom]

Hello,

I have been keeping a planted tank for a couple of years now and I always had a little bit of oil-like substance floating on top of the water. no big deal. Recently though, this layer has gotten thicker than usual. If I agitate the surface of the water (I do not like doing that, since I add CO2 to the water) it seems to clump up in little strands.

Now I know that there are some tricks to get it out. Paper towels absorb it, but it's not very ecologicaly friendly. An air stone would agitate the surface enough to allow the stuff to clump thus allowing the filter to get to it, but I use CO2, so that's not a solution I can use. I have used surface skimmers in the past, but they are generally incredibly finicky to setup, they do not look good to say the least and they generally reduce the flow of the filter a bit and really do not do anything to get at the source of the problem.

I would like to understand where this coating of protein/slime/oil is coming from. This way, I could tackle the problem at its source instead of trying to fix the symptoms.

Do you know where this coating comes from?
Do you know what this coating is made of?
Do you offer any products that can reduce it?

The tank has a capacity of 28US gallons.
Heavily planted (a thick carpet of java moss, some rotalas, vallisneria a couple of cladophora balls).
Not a lot of fish (10-12 amano shrimps as a cleanup crew, 6 harlequin rasboras and of course, like any planted tank, some unwelcomed rams horn snails).
Curently using a Fluval 204 filter with carbon filtration (yeah, I know, a lot ef people say that carbon filtration+plants=no good, but I've been using that since day one and the plants are doing great compared to some other tanks I've seen that use fancy shmancy ion exchange resins).

Thanks!

[Tech Support AN]

I'm sorry to hear about the film in your tank! This is usually a result of high levels of dissolved organic compounds and bacteria, an overcrowded tank, or an overfed tank. The film is made of organics and bacteria (and their waste). You should not be worried because it won't hurt any organisms in your tank. I would recommend doing a large water change to reduce the dissolved organics. There is really no product that will reduce it and I know that you mentioned that you do not like to use a skimmer, but that is going to be your best bet at getting rid of this surface film. I hope this was helpful and let us know if we can be of any further assistance!

[LabTest57]

If it's brown algea, then it's an algea problem - look for solutions to rid algea from your tank.

On the other hand, organic sludge can be reduced or removed by concentrated faculative bacteria that consume/break down proteins, fats, starch, cellulose,etc. Products that conatin such bacteria are known as "Sludge Destroyer" by API, "Sludge Remover" by Kordon, and "Waste Control" by Nutrafin. I've heard good things from Kordon, but Nutrafin sells their stuff way cheaper.

Seachem Stability also has some faculative bacteria, but it's not as concentrated.

Sludge does get removed within a few days, but if you have a big (180 galllon) aquarium like mine, then the sludge will return after a month or so. If not, a week - if you keep very big fish.

So, for small aquariums there are some products that work, but in the long term you will save more with a protein skimmer. Especially, for larger and older aquariums.

[Tech Support JS]

argnom,

If it is an organic problem and you would like an economical solution I would suggest using Purigen. Purigen is not an ion-exchange, but you may still consider it the schmanciest of the fancy resins (at least in quality, not necessarily price), and since it is regenerable it is actually much more cost effective for you than carbon or other psuedo-schmancy resins. Let me explain why I think Purigen would be good for your case: Purigen will specifically and surgically remove organic wastes in your tank without affecting any other components. This will help with your organic buildup problem, while at the same time leaving you worry free of the carbon + planted equation (which, for the record, I run carbon in my planted tank and have never had a problem). Also, Purigen will help polish your water to a crystal clarity. It is often nicknames the "protein skimmer in a bag" and is very, very efficient in removing organics. I hope this information helps!