The Best Aquarium Filter for 1.5 Gallons

It is common for people to believe that no filter is needed for very small aquariums, but the fish do better when they are kept in clean water. While there are many filter choices for large tanks, the options for little tanks are limited. Despite this, there are some good choices that will give the inhabitants of a 1.5-gallon aquarium a clean, healthful living environment.

  1. Filter Basics

    • Some of the basic considerations for a small-tank filter are that it must be strong enough to be efficient but gentle enough that it won̵7;t overpower a tiny space and end up creating too much current. Good choices for this situation are generally those types of filters that fit completely inside the tank. The pump used to power these filters should be either a small pump without too much power or one that can be dialed down so as not to overwhelm the tank. A pump that moves too much air stirs the water excessively and can be overwhelming for the fish.

    Under-Gravel Filter

    • A filter that fits completely under the gravel at the bottom of the aquarium will provide excellent biological and mechanical filtration for a small tank. This type of filter is completely out of sight, but the tubes that rise up from it are visible, normally in one corner of the aquarium. To run the filter, an air pump is connected to one tube and the action of the air causes water to flow down into the under-gravel filter and then up through the vent tubes, trapping debris under the gravel and in the filter.

    Canister Filter

    • A small canister filter placed in one corner of a 1.5-gallon aquarium provides excellent filtration with a minimum of maintenance requirements. The filter floss packing can usually go about two to three months without needing to be replaced. An exterior air pump forces air into the filter, causing the water to move through it, and the filtration material traps debris, thus keeping the water clean. As the filter fills up with trapped material, the flow through it diminishes, and eventually it will stop working until it is cleaned.

    Considerations

    • Choosing between these filters is largely a matter of personal preference, since both types will efficiently clean and circulate the water in a small tank. The canister filter is more effective at cleaning the water, but it takes up a relatively large amount of space when placed in a tiny tank. The under-gravel filter is less obtrusive but not as efficient at keeping the water clean. The under-gravel filter also needs more extensive maintenance than the canister filter, making it less desirable to some owners.