Every aquarium needs a filter—from a 1-gal. Betta tank to a 300-gal. reef environment. If there is a heart to an aquarium, it is certainly the filter. This is, therefore, the single most essential element in a properly functioning aquatic environment. The problem is that it is probably the most complicated piece of equipment to operate. Few people are willing to take the time to study how their tank filter should be set up to work at full efficiency. 

Over the years, I have seen just about every abuse of a filter that you might imagine possible. Standing at the head of this list is the so-called canister filter. With this filter, you can’t see exactly what is happening with the filtration media because it is hidden inside a plastic container. Only the exiting stream of water can give you a clue as to how well the filter is working. And, of course, where do you place this filter, so it will run at maximum efficiency?

From my point of view as a retailer and a long-time fish breeder, I want a filter I can keep an eye on with merely a glance. If the outflow from a canister can be counted on to give you an accurate picture, then that is acceptable, but virtually all canister filters release the processed water through a return hose that has its termination under water. That makes it difficult to tell just how fast the return stream is moving. For a thorough evaluation of the return flow, one must either lift the end out of the water or place your hand into the underwater stream and hope you are a good judge of the water flow rate.



When any customer in your store wishes to purchase a canister filter, try to engage them in a friendly conversation to determine which brand and size of filter will best fit their needs. Gallonage of the tank is not the only factor to take into consideration. The fish load is just as important, if not more so. Large, predatory species are going to require heavy filtration to prevent the water from degrading quickly. You could always un-box a filter and go through an explanation in person. 

Today, that’s the old-fashioned way. Everything you need to learn about how to set up a filter is right there on your cell phone. Some filter brands even have online instructions directly from the manufacturer. If not, there will be a plethora of hobbyists who have posted their opinions about how to set up the filter, including plenty of creative tips and tricks. 

As a retailer, it is highly recommended that you watch some of these videos yourself to be certain that the people giving presentations know what they are talking about. When you find one you really like, recommend it to your customers. 

No matter which sizes or brands of canister filters you sell, it is critical that you have replacements for the disposable items that are used in filters. Of course, people can also buy them online. So, you are going to need a hook that will bring customers back to you for the replacement cartridges, pads, carbon sacks, sponges, etc. Pricing is one way to accomplish this, but I prefer a punch card that will provide additional filter materials at a discount. This card can apply strictly to the items in question, or it can be tied to money spent no matter what items the person bought. 


Types of Filters

Now, for tanks up to 55-gal., I usually recommend over-flow filters. Above that gallonage, I personally prefer canister filters—up to a point. Once you reach 90-gal. and beyond, you should probably use two canister filters, or you can take the next step into filtration and go with a sump. This will require a substantial capital outlay for the tank owner. 

There are two ways to go in this situation: (1) a drilled tank with one or more overflows or (2) an overflow box. For years, I would use only a drilled tank, but I was gradually won over to overflow boxes since they take up virtually no space in an aquarium. They are perfect for freshwater environments or fish-dominated marine tanks. 


Diving into Sump Filtration

Tanks that are four feet or longer and eighteen inches wide or wider can benefit greatly from sump filtration. To start, the overflows need to be at opposite ends of the tank. If there is only one overflow chamber, the return should be bifurcated, and the overflow located dead center on the back wall. With an internal overflow (or dual overflows) there is always a chance that something can go wrong. In my many years of using sumps, I have only had one instance where any significant amount of water drained out of a tank and onto the floor.

Now, are sumps for everyone? Of course not, but everyone can employ a sump with great success if they practice good tank maintenance habits. Let’s take a closer look at sumps and discuss the options they provide.

Whether a tank has overflows or an overflow box—once water reaches the sump –everything works the same way. From my point of view, sumps are superior to every other type of filtration for a number of reasons. First, they are totally out of sight except for the well-concealed overflows. Even an overflow box can be placed so it is unobtrusive. If you have the hoses under the tank or those coming from the overflow hose properly clamped, they are never going to come off. Even if the hose itself starts to leak, it’s never more than a pinhole leak.

A question arises: are there drawbacks to customers using a sump instead of a mechanical filter like the canister or overflow models? Well, yes, this diminishes or removes the need for customers to use proprietary filter cartridges. All they require along these lines are a set of backup filter socks and a “bubble-trap” sponge that can be rotated out whenever the tank owner sees fit. With this in mind, I have seen non-reef stores phasing out or greatly reducing the number of sumps they carry for freshwater customers. That is a decided mistake on their part as far as I am concerned. You are in business to make money, but if you can’t serve customers in an honest way—you should rethink your sales strategy. 

Finally, don’t forget sponge filters that are run by an air pump or even an underwater motor. With proper aquarium maintenance these simple filters can do a great job in a Betta tank or an environment with shrimp and miniature fishes. PB


Edward C. Taylor has been in the pet industry for more than 40 years as a retailer, live fish importer and wholesaler, and fish-hatchery manager.