Using a sump to filter your aquarium is the most effective way to employ high-performance filtration gear and increase the overall water volume of your aquarium but we realize this is not an option for everybody. Sumps can be bulky, expensive, and will require a bit of experience with plumbing to set up properly.

That is precisely why hang-on aquarium equipment can be a real lifesaver, even for saltwater aquarium owners! Especially for those of you building a tank on a budget or looking to move beyond your all-in-one nano but are not quite comfortable installing a sump system. 

Benefits of Hang-On Aquarium Equipment

  • Easy to maintain
  • Quick to install
  • Space-saving
  • Affordable

We put together a list of some of our favorite hang-on style equipment that we find most valuable to modern tank owners and defined the important qualities to look for when choosing a particular piece of hang-on filtration for your aquarium.  

Hang-On Power Filters

Hang-on power filters have been around since long before my time in the aquarium hobby and are very popular because they are much easier to maintain compared to the alternatives - submersibles and canister filters. They are easily retrofitted onto almost any aquarium and don't require much knowledge or experience to install and operate.

Some key components to look for when choosing a power filter are a sufficient flow rate that can completely cycle your entire tank volume about 3-5 times per hour and a nice large media chamber that will accommodate different types of filter media. When used on a saltwater aquarium, you also want to be sure you can easily access the pump and impeller for regular cleaning.

Power filters do have some limitations because they are only so big. I wouldn't expect a power filter to effectively support saltwater aquariums any larger than 70 gallons. While you can use multiple power filters on a single tank to improve filtration capacity, there becomes a point at which money is better spent upgrading to a sump.

Hang On Reef Tank Equipment Seachem Tidal Filter

The Seachem Tidal Filter is one of the best choices for saltwater aquariums for a few reasons.  It has a large media chamber to accommodate filter media of your choice or you can simply stick to the various media available directly from Seachem. The included pump is equipped with adjustable flow and a surface intake allowing you to remove proteins that tend to collect on the surface of the water.  There is also a convenient maintenance indicator which simply notifies you when the flow rate through the media chamber has been reduced, indicating the filter media is clogged and needs attention.

Hang-On Protein Skimmers

A protein skimmer is technically another part of your filtration system and is a crucial component for saltwater tanks because it will remove dissolved organic compounds and help to oxygenate the water. When used side by side with a quality power hang-on filter, you can effectively filter a mixed reef aquarium, complete with fish, invertebrates, and corals without compromising water quality.  

Manufacturers have been refining and engineering hang-on style skimmers for years and have come up with some very unique designs but regardless of which brand you prefer, the facts remain that you want a skimmer that has a large reaction chamber and a high-quality pump to achieve the best performance. Being a protein skimmer, an overflow can be dreadfully messy spilling water onto the floor so having some kind of drain on the collection cup is also a valuable feature.  

 

Hang On Reef Tank Equipment HOB 1.5 Protein Skimmer

 

The AquaMaxx HOB-1.5 is reputed to be one of the best hang-on skimmers ever made and has ranked among the best-selling hang-on skimmers since its introduction in the early 2000s. The HOB 1.5 maximizes the space behind your tank with a large rectangular reaction chamber that is powered by a quiet and reliable Sicce brand needle-wheel skimmer pump. The Sicce pump is retrofitted with a bubble diffuser and produces a dense foam that is capable of pulling organics, even with a limited contact time.  It is made from 100% acrylic and comes in a stylish royal blue color that won't take distract from the overall aesthetic of your aquarium. 

The collection cup is easy to remove and includes a drain fitting that you can either direct right back into the skimmer itself or run a piece of tubing to a separate collection chamber to prevent an accidental overflow in the cup. Adjustments are easy, simply slide the cup up or down to fine-tune how much skimmate you want to collect. An air adjustment valve can be added to the airline if you wish to further tune the air and there is also a bubble stopper accessory that can help reduce micro-bubbles from being released back into the display. 

The HOB 1.5 is best used on tanks from 30 - 70 gallons depending on the bioload. AquaMaxx also makes the Bullet-1 nano-skimmer for tanks under 30 gallons as well as the ConeS HOB which is a much bulkier hang-on skimmer rated for tanks over 75 gallons.  

Multi-Filters

Multi-Filters are like a power-filter and protein skimmer combo, a single filter module that includes both a protein skimmer and a filter media chamber.  While these filters never really gained too much momentum over the years, they do have a place in aquariums where space is limited.  

 

AquaMaxx Multi-filter

The AquaMaxx HF-M is a large multi-filter that incorporates a protein skimmer, media chamber, and a configurable area that can be used for a heater or refugium. This ultimately allows you to combine almost all of your life-support gear into a single device. You won't need to have a separate skimmer and filter and you won't have to submerge the heater directly into your display. 

The HF-M is 100% cast acrylic and utilizes a single Sicce pump that is retrofitted with a bubble diffuser to feed the skimmer and move water through the filter. There is a clear panel on the backside that allows you to add a refugium light should you wish to forego the heater installation.  The collection cup is almost identical in design to the HOB 1.5 with the included drain fitting to prevent accidental overflows.  The pump is also located inside the body of the HF-M so you won't be dealing with a bulky pump inside your display. 

Media Reactors

Media Reactors are specifically designed to maximize the efficacy of filter media such as carbon and GFO. Some reactors are even suitable for Biopellets so long as you supply sufficient water flow. There is a wide selection of hang-on style media reactors on the market and they require the use of a small powerhead to feed water through the reactor. The powerhead sits inside your tank and then pushes water through the reactor hanging on the back via some flexible tubing. The installation is not always the best looking when directly on the display tank but they can be great for intermittent use. 

When shopping for a media reactor, you need to have a compatible hang-on bracket which is sometimes sold separately from the media reactor itself. A pump, ball valve for flow control, flexible tubing, and filter media of choice are also required for installation and are not often included with the reactor

 

Media Reactor

 

The AquaMaxx FR-SE is perfect for hang-on applications because it includes a bracket and a tube holder to keep the plumbing in place when hanging off the back. Just pick up a small powerhead such as the Sicce Syncra Silent 1.0, 3-4 ft of 1/2" flexible tubing, and a 1/2" ball-valve to complete the installation.

The Two Little Fishes Phosban Reactors are also suitable for hang-on applications right out of the box.  They also sell a convenient extension kit with 90° elbows which makes the hang-on installation much more streamlined. 

Refugiums

Refugiums are very popular for saltwater tanks because they help export nitrate and phosphate via the growth of macro-algae and also provide a refuge for beneficial micro-fauna to propagate that help clean up waste and sustain a natural food chain in the aquarium. Refugiums are all about size, the larger the refugium, the more macroalgae you can grow at once and the more nitrate/phosphate you can remove. The attitude is most often, the larger the better if nutrient export is your ultimate goal.

Hang On Refugium

CPR, Fiji Cube, and AquaMaxx all make great hang-on refugiums that are available in multiple sizes to accommodate various tank sizes. The CPR refugiums require the pump to be installed directly inside your display tank to push water through the refugium chamber while the Fiji Cube and AquaMaxx refugiums are designed with the pump located inside the refugium itself. No matter which option you choose, you will need to get an appropriate refugium light to illuminate and support the growth of macroalgae. We really like the Tunze Eco Chic and Innovative Marine ChaetoMax lights because they are super easy to retrofit onto these hang-on style refugiums.