With very similar skimming capabilities and only a $20 difference in price, some aquarists have a tough time deciding between the DOC Skimmer 9410 and the DOC Skimmer 9011. From the outside they appear to be from different planets in the protein skimmer universe.
The DOC Skimmer 9410 (top left) looks like what most people have come to expect protein skimmers to look like. It has a cup on the top, a pump on the side and a stand pipe next to that. It’s high quality clear acrylic with the fit and finish people expect to come out of Germany. Like most skimmers on the market it has everything exposed for you to see. The pump is right there, you can look in and see the bubble column… nothing is hidden from view.
But the 9011 keeps it all hidden. It is a simple, dark, unobtrusive box, following the classic form of our Comline series of filters. It has an internal pump and can be used in-sump with the included stand pipe sump kit (pictured below) or else in-tank without it (as it’s pictured above). For in-tank protein skimmers, it is the best on the market.
The 9410 is the more powerful of the two. It’s powered by a pump from our Hydrofoamer series (pictured below) which uses a needlewheel/Venturi combination to inject a dense column of tiny bubbles into the reactor. It’s by virtue of the needlewheel that the 9410 is able to produce bubbles which are, on average, smaller than those of the 9011. Smaller bubbles equates to a greater total bubble surface area which translates, loosely, to higher performance. This also makes it more electrically efficient, consuming 15 watts to the 9011′s 22.
The 9011 does not have a needlewheel. It relies on a permanent-magnet centrifugal pump (below) coupled with a carefully engineered Venturi to introduce air into a column of water. This allows the 9011 to process more water in the same amount of time, but not quite as thoroughly as the 9410. It does however give it a different advantage- a slight reduction on the decibel meter. The 9410 has never been described as loud, but if absolute silence is the target you are shooting for, you’ll hit closer to it with the 9011.
Another of the 9011′s advantages is that it can be used both inside the display aquarium or else down in the filter sump. This versatility can come in very handy if, for example, you plan to have a simple sumpless aquarium now, but foresee changing to a system with a sump in the future.
And one final distinction is that the 9011 has been designed to be more tolerant of changes in the water depth. It will operate quite happily at any depth between 4 and 11 inches. But the 9410 is like most protein skimmers in that it prefers to stay in water that’s a consistant depth. That can be anywhere between 5.5 and 9.5 inches, but it will require an adjustment if the level changes by much.
So there you have it, the main differences between the 9410 and the 9011 DOC Skimmers. While the 9410 does have a performance advantage, the 9011 has many of its own talents that deserve consideration.