Protein Skimmers Do You Really Need One?
By Tony Griffitts
Protein skimmers have been around a long time and within the last decade or so, manufacturers have made great improvements in their efficiency. A good protein skimmer can cost several hundred dollars with a pump. Today there are a growing number of reef keepers that are very successful running their reef tanks without one. We need to question why these tanks are doing so well.
I have run many marine fish only and reef aquariums with and without protein skimmers for many years. To this day I can not say that there is a noticeable benefit running a protein skimmer. I ran a protein skimmer for many years on a fish only system and then I took it off the system. The system was ran for years without a protein skimmer and there was no noticeable affect on fish health. I have also set up many reef systems without protein skimmers, and had excellent results with small polyp stony (SPS) corals growing very well, and several species of marine fish spawning. Some reef system setups had undetectable nitrate levels after being set up for years.
Why are these systems doing so well? In reef systems, you only need to look at the macro and mirco-creature inhabitants. Many of these creatures are filter feeders that process the same proteins that protein skimmers remove from the system. When a deep sand bed (DSB) is used in the system it can be heavily colonized by these filter feeders that help with water exchange through the sand bed. The slow exchange of water through the sand bed in turn helps greatly with natural nitrate reduction (NNR). This can help explain why some reef tanks without protein skimmers have undetectable nitrate readings. When you run a protein skimmer on a reef tank you are essentially removing a food source for these creatures, there by effecting the population the system can support. Many marine hobbyist that set up their system from the beginning with protein skimmers often notice a substantial decrease in the amount of foam they collect after the system has been set up for several months. Many of them begin to think that their protein skimmer is not working as well anymore, even though the flow rate and bubble production looks the same. This can be attributed to the fact that filter feeders have started to heavily colonize the system and are now competing with the protein skimmer for proteins.
Filter feeders that live in a deep sand bed take up proteins as a food source, and as an added benefit they help with natural nitrate reduction.
In systems where there is no DSB or fish and/or invertebrates that would feed upon the filter feeders that live in the sand bed, a protein skimmer will probably have some benefit on water quality, as far as oxygen caring capacity and nitrate/phosphate accumulation. These benefits can also be realized with large regular water changes.
Protein skimmers on live rock curing tanks are still a great benefit, as the process of curing live rock kills many filter feeding organisms. When there are no filter feeding organisms the best way to remove proteins is with a protein skimmer.
The theory behind running a protein skimmer on a marine aquarium sounds good, but in reality its impact on well established marine aquarium appears to be minimal. Real independent research needs to be done to validate the value of running a protein skimmer on a marine system. With all the examples of marine aquariums that are doing exceptionally well without protein skimmers, I am finding it harder and harder to justify the expense for all marine aquariums.