Fish Supplies

Having the right supplies is integral to fish keeping. Stay well stocked and keep a clean tank!

Aquarium fish keeping is a complex hobby that is, in my opinion, perfect for those who love science and loved science fairs as a kid- Or who are enchanted enough by the beauty and tranquility a tank brings to learn about maintaining them.

It’s definitely not as straightforward as a hobby like running. You don’t just grab your shoes and jacket and go. There are lots of components and “moving parts” to learn about that take some getting used to in the beginning.

One way to get oriented to all of the components in this hobby is to understand the supplies that are needed. We’ve compiled a glossary of common fish supplies with their definitions and uses. Feel free to refer back to this as needed while you learn!

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Aquarium Supplies

Alkalizers and acidifiers:

Maintaining water parameters is one of the most important aspects of keeping your fish alive and healthy. Sometimes, you’ll need a little extra help by way of alkalizers and acidifiers. These help correct water hardness and pH.


An overlooked aquarium maintenance stable that comes in handy when you need it! Whether you’re siphoning, transferring, or cleaning, a bucket has got you covered.

Capture nets:

Sometimes you have to gently capture your little (or big) fish friend, and you’ll need a capture net to do it. It’s a crucial tool for taking care of fish, acclimatizing, and more. One tip is to keep a variety of net sizes on the end so as to make it more convenient in the moment.


This one is pretty self-explanatory: most people decorate their tanks, although the decor can vary significantly depending on the type of tank it is (saltwater, freshwater, planted tank, nano tank, etc.). Decor is usually composed of plants, rocks, wood or logs, and aquarium products like a fish house or a submarine that provides your fish with places to hide or burrow, depending on the species. Saltwater or marine tanks will often have invertebrates like coral as part of the decor.


Okay, sometimes as an aquarium fish keeper you’ll encounter some fancy tools. These two are great examples. Densimeters measure the density of a liquid, while refractometers do the same thing but a different way, using light refraction to measure the water’s density. (Remember what I said about the science fair kids?!)

Drying cloths:

Aquarium fish keeping is a wet hobby. Keep cloths on hand at all times to soak up excess water, especially during cleaning and maintenance.


You can’t keep an aquarium without a filter. A filter is crucial and keeps your fish alive. Filters remove toxic compounds from the water such as the buildup of nitrates and ammonia, which can kill your fish. They aerate the water and keep it clean. The three main types of filters are canisters, foam filters, and HOB filters.


This is a huge topic in and of itself, but feeding your fish correctly is very important to ensure their health and longevity. Food comes in all different forms from flakes to pellets to live food such as brine shrimp, and the type and amount of food should accurately match the species of fish you’re keeping. To learn more, you can check out our write up on nutrition here.


A heater is also an aquarium necessity; it prevents the water from getting too cold for the fish, and also keeps the water temperature stable. It’s especially important when keeping tropical fish. One great tip is to keep two heaters in the tank at half strength each, so that if one fails, do you have time to catch it before the tank temperature plummets.


Lighting will depend on the type of tank you have and the type of fish you’re keeping. It’s particularly relevant for marine or reef tanks that have corals with specific lighting requirements. Additionally, many freshwater fish rely on light to indicate whether it’s daytime or night time. For planted tanks, the species of plants will determine the light requirements as well.


Siphons are essential for cleaning an aquarium; debris and decaying matter can build up in the substrate overtime, and the store is like a water vacuum that pulls out dirty water and debris.


This is just a fancy word for the material at the bottom of the aquarium. Different materials can be used depending on the type of tank, from sand to small gravel to large pebbles. The type of fish you’re keeping will determine the substrate, as well as preference.


Can’t have an aquarium without one. 😂 This one is self-explanatory. Be aware that not all tanks are created equal and that summer better than others. Also be aware that water is HEAVY and that it’s important to have a stable, heavy duty, and non-moving base.


An aquarium is a tiny ecosystem that you’re responsible for maintaining. Everything that leaves in the aquarium requires specific conditions to survive and thrive. In order to make sure that you’re providing the correct conditions, you perform regular tests on water quality to keep it stable. The type of tank will determine what test performed, but the most common are tests for ammonia, chlorine, hardness, PH, and nitrate.


Most heaters have a built-in thermostat. A thermostat just determines the temperature of the water and will shut off the heater when it reaches the specified temperature.

Water conditioner:

Water conditioner is used to correct undesirable water parameters, because it removes harmful chlorine, chloramine, heavy metals, etc. from the aquarium water.

Saltwater Tank Supplies

RO and ID filters:

Reverse osmosis and deionization filters are two specialized, extremely high-quality water filters that are used for saltwater aquariums. People also use them for freshwater aquariums, and for their own drinking water at home.

Saltwater decorations:

For marine tanks people often use decorations made of limestone because they help maintain the water hardness. Corals can also be part of saltwater decor.


This is a kind of filter used specifically in saltwater aquariums to remove excess proteins before they have a chance to break down into potentially harmful substances such as nitrogen.

Specific lighting:

Saltwater aquariums often require specialized lighting, in particular for invertebrates like clams and corals.

Temperature control:

Temperature maintenance is an issue in marine tanks since they are usually warm and less require heaters; It’s a good idea to have a temperature cooling system like chillers as well.

Water + Salt:

You can’t just go around throwing any old water into a saltwater tank. The water in marine tanks is composed of pure water (without mineral content, such as reverse osmosis filtered water) and specialized salt mix which you can purchase at your local aquarium store.


As you can see, there are many different pieces of equipment that you’ll use as an aquarium keeper. It’s a hobby that requires specific equipment in order to properly maintain your tanks.

So while it might not be as “grab and go” as a hobby like running or playing tennis, it’s very rewarding once you have set up an entire aquatic ecosystem in your living room! And getting oriented towards fish supplies is the first step:)