Protein skimmers all follow one general concept, in that they remove proteins from the water. But there are different methods implemented to do so.
The basic concept is that tiny bubbles of air are introduced into the water, which brings the organic materials to the surface to be pushed into a collection cup (foamy!). We are going to take a look at the different methods used to do this.
The Different Types & Technologies of Protein Skimmers
Nearly all common types of protein skimmers can pretty much be categorized within these two categories Co-Current & Counter-Current.
What’s the difference?
- Co-current designs introduce the air flow at the bottom of the skimmer unit, flowing upwards with the water current. Basically, the air is flowing the same direction as the water.
- Counter-current designs introduce the air flow against the water flow, pushing the air against the water current. This allows the air bubbles to flow against the water for a short period of time before following with the flow of the water, which in theory gives the air bubbles more contact time within the water. Some argue that this makes counter-current systems more effective.
Now that we’ve covered the two basic categories, let’s take a look at the different types of technologies within these categories.
1. Venturi Protein Skimmers (co-current)
This is a popular protein skimmer technology that utilizes a venturi pump to introduce air to the water. The water flows through the venturi pump, air is introduced, and the water/air mix flows into the main skimmer chamber. From there, the foam overflows into the collection cup.
2. Air Stone Protein Skimmers (co-current)
This type of protein skimmer is the most basic, and even though it can work, it may not be as effective as newer protein skimming technologies. The idea is that an air stone is used to create micro bubbles, and the water flow it pushed through these micro bubbles. It’s a very basic concept.
3. Aspirating Protein Skimmers (counter-current)
This technology uses pin-wheels or mesh-wheels (like an impeller) to mix air and water – the air/water is mixed directly by the impeller. The mixture is typically forced downward into the skimmer body and then the bubbles (and foam) rise to the top and flow into the collection cup.
These types of skimmers are pretty popular, and can come in pretty compact sizes for smaller aquariums. Many different brands make this type of protein skimmer.
4. Downdraft Protein Skimmers (counter-current)
These types of skimmers drive a current of water down into tubes or chambers that contain bio balls or other plastic media. This mixes the air and water effectively, and foam is pushed into a collection cup.
5. Beckett Protein Skimmers (counter-current)
Beckett skimmers work much like downdraft skimmers, but they don’t use plastic media to mix the air and water. A foam nozzle is used to make the air bubbles, and the stream is forced down into the skimmer chamber.
6. Spray Induction (counter-current)
This technology is patented by AquaC, and is only available in their skimmers. This works similarly to the downdraft/Beckett skimmers. A spray nozzle is fixed above the water levels and the water/air mix is pushed down through the skimmer body and foam rises into a collection cup.
Is your head spinning yet? If so, just think of it like this – all of these technologies are designed to mix air and water, creating foam, which rises and flows into a collection cup. The specific way in which these types of skimmers do that may vary, but that’s what it really comes down to.