Protein Skimming is the Most Important Sump-Based Filtration Method
Once you understand what a sump is, it’s time to understand what filtration devices can go in a sump. This article will look at the most common in-sump filtration device—the protein skimmers. After this, you could look at other sump-based filtration, including fluidized bed filters and chemical filtration.
Most modern saltwater aquarists would not run a marine aquarium set-up without a protein skimmer. Often the protein skimmer—a tall cylinder usually made of acrylic—is placed directly in the first chamber of the sump and powered by a submersible pump (powerhead), which forces water into the cylinder. In the simplest terms, bubbles are injected into the skimmer creating an interaction between air and water inside the cylinder. The density of bubbles becomes highest at the top of the skimmer, and that is where foam forms. It is this foam that then transports organic pollutants to the collection cup where they can be completely removed by the aquarist during regular maintenance.
When considering which protein skimmer is right for your system, the question you must ask yourself is which protein skimmer can provide the most efficiency. A protein skimmer’s efficiency can be measured by the amount of skimmate (organic waste) produced for the amount of energy used. Most aquarists will also consider cost of the protein skimmer as a factor in their purchasing decision.
There are many different methods of skimming employed by various companies (and even various models within a company). In other words, not all skimmers are born equal. You’d need to have firsthand experience with all the various methods to make a solid recommendation.
I personally have used every single skimmer technology out there from counter current back in the day to the new re-circ skimmers popularized by EuroReef. I have come to the conclusion that certain technologies work in certain applications.
Best Protein Skimmer
Here are some personal recommendations, based on system size, skimmer efficiency and cost:
Systems Less than 200 Gallons
Needle wheel venturi skimming is the best. You can throw re-circ skimmers in there as well, because they are basically just fancy needle wheel venturi skimmers. In this class, I like the ASM skimmers because of the cost versus skimmate equation.
Systems Between 250 and 1000 Gallons
Spray Injection is best. It is sort of a waste on smaller tanks, otherwise it would be in the above class as well. This is my personal favorite type of skimming. It is simple, no complicated parts to clean, nothing to fail, easy adjustments. The big issue for people is usually the pumps recommended for these skimmers. The pumps have to be pressure rated and be powerful. The pump of choice currently is the Iwaki line which can be expensive. In this class, the only choice is the Aqua C line, which is my absolute favorite skimmer.
Systems Over 1000 Gallons
The only choice still (it has been for years) is Beckett Injection, which is basically a fancy venturi system. They require extreme power to perform well, but no other technology can process more water at a time period. They are an absolute pain to work with, but people who have these sometimes-20-foot-tall-skimmers, have full time employees to maintain them. For home use, I like the Precision Marine line for no other reason than they are inexpensive compared to the commercial equivalents and are extremely well made.