Aquariums and Zoos,  Careers,  How-To's,  Learning Resources

Aquarium-Keeping: Diving Into the Science and Art

Aquariums are windows into a whole new world—one full of water and opportunity. Some people like to build fortresses and cities in the popular videogame Minecraft, while others like to build real-life worlds. No matter how daunting aquarium building may seem, it’s a hobby with a niche for everyone. With just a basic understanding of biology and a splash of creativity, you too can delve into the world of aquarium-keeping.

At its core, being an aquarist means understanding the nitrogen cycle and basic fish behavior. However, you may be wondering, what, in fact, is the nitrogen cycle?

Cycle of Life

Well, the nitrogen cycle is just a fancy way of saying fish poop, and bacteria clean it up. Really, it’s that simple. Fish produce waste, and nitrifying bacteria work to convert the byproducts of this waste into less harmful products. For example, fish poop and excess fish food produce ammonia, which is toxic to fish. Bacteria then work to convert this ammonia into nitrite and then into nitrate. Nitrate is a far less harmful product that plants actively absorb and process. By facilitating a healthy nitrogen cycle, you can help keep healthy fish.

At the end of the day, improper nitrogen cycling is the core problem of most tanks. If a tank never reaches equilibrium and struggles to catch up with the nitrogen cycle, it can stimulate further health concerns and pose even more serious water issues.

My 10-gallon fish tank. Photo Credit: Kelsey Fleming.

The Freshwater or Saltwater Conundrum

Firstly, it’s important to understand what kind of tank you want. Do you want a freshwater system? Maybe, a saltwater system? Weighing the pros and cons of each will get you one step closer to aquarium-keeping.

Between freshwater and saltwater systems, there are various differences in care and maintenance. For instance, saltwater systems require consistent salinity. Even though removing saltwater from a saltwater system may seem simple and straightforward, it poses many risks and concerns for aquarists looking to refill the tank.

Since water regularly evaporates, salt crystals can build up in a tank. For this reason, you’ll mainly need to refill a saltwater tank with freshwater. Maintaining salinity may be a rigorous balancing act, but it is important in helping your aquarium grow and expand.  

Saltwater tanks also tend to be more expensive from a maintenance supply standpoint, as well as a biological standpoint. In addition to being some of the most colorful and charismatic fish, saltwater fish tend to be more sensitive and cost more.

Additionally, there are other costs to take into consideration for saltwater tanks. For example, other necessary supplies, include items, like protein skimmers, salt, live sand, etc.

For our purposes, we’ll be focusing on freshwater aquariums. As you start out in the hobby, freshwater aquariums can help you learn and master the basics before pursuing even more complex systems, like saltwater tanks.

‘Choose Your Own Adventure’: Aquarium-Keeping Edition

In the world of aquarium-keeping, there are peaceful tanks, and there are aggressive tanks. For instance, you may want to build a planted world full of schooling tetras, African dwarf frogs, and snails. OR, perhaps, a tank full of intimidating cichlids is more your style. At the end of the day, it’s a personal preference.

For the beginner aquarist, guppies and bettas are great fish to home first. Guppies are colorful schooling fish that many enjoy. Whereas, bettas are colorful, yet more aggressive fish. Bettas thrive best in larger tanks, even though they can live in smaller spaces. I recommend using a minimum 10-gallon tank for a betta. That way you have flexibility with tankmates. Some tankmates to consider include ember or neon tetras, cory catfish, shrimp, and snails.

My male betta with an amano shrimp. Photo Credit: Kelsey Fleming.

No matter what you choose, you’ll want to set your tank up for success. To do this, you’ll need to gather the right supplies and do proper research.

Setting a Strong Aquarium Foundation

To start, get yourself a nice, sturdy tank and tank stand. Small tanks tend to be more difficult to take care of, so novices typically benefit from 10 gallons or more tank set-ups. The reason why larger tanks may be easier for beginners is that you will have to do less frequent water changes, and the water chemistry will stay balanced over a longer period of time. The waste in small tanks can build up quickly, causing the water quality to jump all over the place.

People often overlook tank stands, but these are extremely important when putting a new aquarium together. Every gallon of water weighs nearly 10 pounds. Therefore, a 10-gallon tank can easily weigh over 100 pounds with water and décor. Make sure you choose a tank stand that is capable of keeping your aquarium steady and safe.

When you first take this tank home, make sure you test it for leaks. Fill it slightly with water to see if there are any weak spots. Finding a leak, later on, can de-rail your whole plan, so try to catch these issues early in the process.

As you set up your tank, make sure you place the tank in an area out of direct sunlight. If the tank sits in a space with too much sunlight, algae blooms can occur, turning your water green and murky.

Next, you’ll want to grab yourself a good filter. Filters consist of physical and chemical barriers. The filter, itself, will prevent detritus from circulating in your tank, while the contents of the filter, such as charcoal, will work to purify the water.

To keep your water temperature in check, pick up a good heater, preferably an adjustable heater. Having an adjustable heater will come in handy if you ever need to raise the temperature for fish experiencing illnesses, like ich. Ich, a parasitic infection, is the fish equivalent of human chickenpox. When fish succumb to ich, they get small white dots all over their bodies. Oftentimes, it is a symptom of stress.

Now, to one of the more fun parts of aquarium-keeping. You’ll need to pick out gravel or sand for your tank. Over time, this substrate will become a home for the beneficial bacteria fueling the nitrogen cycle. Alongside substrate, you’ll need décor. Here, you can really customize the tank to your liking. For instance, you can choose from a range of items, like aquatic plants, driftwood, plastic plants, rocks, castles, etc.

My tank customized with plants, rocks, and a moss ball. Photo Credit: Kelsey Fleming.

Welcoming New Neighbors to Your Aquarium

Once you have everything picked out, you’ll need a game plan for the water. Some people choose to fill their tanks with spring water, while others prefer tap water. However, if you decide to go the tap water route, you’ll need to grab a water conditioner. A water conditioner is essential for dechlorinating and detoxifying tap water. Because chlorine is toxic to fish, it’s important to eliminate it while you’re setting up your tank.

Speaking of water treatments, you’ll want to consider grabbing a biological booster. Biological boosters provide bacteria for your tank while it’s starting out. In the early stages, tanks can struggle to establish steady levels of bacteria. That’s where biological boosters come in handy. With these boosters, you can jumpstart the nitrogen cycle and get a few steps closer to introducing fish.

Many aquarists want to immediately add fish to their tank. However, this is where the trouble can start with aquarium-keeping. Even though it’s tempting to run down to your local fish store and grab all the fish you want, setting up an aquarium is a game of patience. Because your tank is new, it has not had the time to build up bacteria and appropriately engage in the nitrogen cycle. Until your tank has started to build up adequate levels of bacteria, it is best to refrain from buying fish.

If you choose to introduce fish too early on, you risk what aquarists call “new tank syndrome.” When “new tank syndrome” strikes, ammonia and nitrite skyrockets. This situation is a symptom of inadequate bacteria. Without beneficial bacteria, harmful toxins can’t properly break down and cycle through the ecosystem. As a result of “new tank syndrome,” fish often die in large numbers, leaving young hobbyists distraught and frustrated.

Early Struggles of Aquarium-Keeping

To avoid the trials and tribulation of “new tank syndrome,” it’s important to cycle your tank for 1.5 weeks to 2 weeks, so bacteria have an opportunity to accumulate. During this time, some people choose to add pinches of food into the tank, so the bacteria can get going.

But, what exactly does it mean to “cycle” a tank? Simply put, cycling a tank means plugging in the heater and filter and letting the water do its thing. Since it’s your little world you’re building, it’s hard to not be involved in every step of the process. Even though this step seems less involved, it’s one of the easiest and most important parts of aquarium-keeping.

After about 1.5-2 weeks of cycling your system, you’re almost ready to welcome fish. When deciding what fish you want, you’ll want to consider exactly what you value. Would you like social or antisocial fish? Colorful or camouflaged fish? Fish looking to stay the same or fish looking to grow over a foot long? Regardless, there are numerous options. So, make sure you carefully craft your plan.

Before introducing these new fish, make sure to perform a water test. From this water test, make a note of ammonia, nitrite, and or nitrate level. By testing your water, you’ll have a better idea of just exactly where you stand.

Pro-Tip: Many local aquarium shops provide free water testing. Therefore, bring in a sample of water, and save yourself the time and money of personal water testing.

When you introduce your new residents to the tank, properly acclimate everyone. While some fish require just a few minutes for acclimation, some require hours of a process called, drip acclimation.

For most freshwater fish, you’ll only need to float their bag at the surface of the water for 20-30 minutes before releasing them into the tank. When you release them into the tank, try to limit how much of the bag water gets into your system. This is simply a precaution, so you’re not cross-contaminating your tank with other kinds of bacteria and parasites.

Maintaining Your Aquarium

Now that you’re on your path to being an aquarist, it’s important to learn what is required for aquarium-keeping. For example, for a basic 10-gallon aquarium, you’ll need to perform monthly water changes. During a water change, you’ll use a siphon, otherwise known as a gravel vacuum, to suck up old water and algae. Just like a vacuum, this siphon works to pull up algae from the substrate, giving your tank a fresh look and a lower nitrate count.

In addition to water changes, you’ll need to scrub algae on the tank and décor. Over a brief period of time, algae can build up, leaving green, brown, or, even, red films of algae. To best scrub algae, you’ll want to use scrubbing sponges specific to the kind of tank you have. In the world of aquarium sponges, there will be ones for acrylic tanks and ones for glass tanks.

Pro-Tip: Acrylic tanks can often be difficult to clean. From personal experience, I have noticed algae clings to acrylic more than glass. So, if you’re in the market for a tank, save yourself some time and grief and go with a glass tank.

If you’re looking for a more natural way to clean algae, consider adding some snails or shrimp to your habitat. For example, snails will roam across the sides of the tank and across any plants you may have, sucking up algae. When it comes to the nooks and crannies, shrimp do a great job of getting into the corners of plants and rocks. With these guys on your team, your tank will look clean and spiffy in no time.

Gold Inca snail in my betta community tank. Photo Credit: Kelsey Fleming.

From time to time, you will also need to adjust your filter. Many filters require cartridge replacements, while some require charcoal, ammonia remover, and/or foam insert changes. Make sure you understand the contents of your filter well, so you can keep it fresh and running.

When it comes to aesthetics, you’ll want to regularly prune the live plants in your aquarium While some use plastic décor, some may prefer live plants. If you’re looking for that extra step of biological filtration, live plants should be a major consideration. With the live plant route, you’ll want to make sure you are properly taking care of these plants. Plant care involves regularly scrubbing leaves and stems, providing fertilizer if need be, and/or using carbon dioxide. Since aquatic plants utilize photosynthesis for energy, carbon dioxide acts as life fuel.

Biology in Motion

Now, for the stars of the show… your fish. Fish will require your attention. Depending on the species of fish you house, you’ll want to customize your feeding schedule and ingredient list.

For many fish, they will require feedings 1 to 2 times a day, while some prefer 3 separate feedings a day. Whenever you perform a feeding, ideally turn off the filter and limit how much food you’re adding to the system. Because food is a major contributor to water chemistry imbalances, you’ll want to add a small pinch of food to the tank. If the fish consume all their food and seem hungry, add another small pinch of food. However, as you feed your fish, try not to go past 2 minutes for the total feeding time.

Speaking of water chemistry, keep an eye on your tank with regular water testing. Water tests should examine nitrate, nitrite, ammonia, hardness, chlorine, and salinity. Most testing strips will analyze these factors. By understanding these water parameters, you will better understand the quality of your tank and the behavior of its inhabitants.

Keeping Everyone Healthy

The health of your tank’s residents should be paramount. First and foremost, you’ll want to direct any health concerns to a veterinarian. The following is for knowledge purposes only and is not meant to diagnose or treat any health issue.

To keep everyone healthy and happy, you’ll want to keep a good eye on their appearance and behavior. For instance, for fish struggling with water ammonia issues, you’ll often see them gasping at the surface. Other health issues include ich, popeye, etc. For those with ich, you’ll see those chickenpox-like white dots we talked about, while those with popeye will suffer from bulging, swelling eyes.

To curtail these health concerns, you may need to set up what we call “hospital tanks,” otherwise known as isolated tank systems. Or, perhaps, you’ll want to just perform dips. For example, you may want to dip your sick saltwater fish in freshwater. Before doing this, make sure you match the temperature of your freshwater water to the temperature of your saltwater water. To do this, float a small bag of freshwater in your saltwater tank for 20-30 minutes. When dipping your saltwater fish in freshwater, be mindful of how long you do this. Always monitor your fish during this process.

If you’re not observing any considerable differences using the dip method, you may want to turn to the “hospital tank” method and use a variety of water treatments depending on the issue. When treating tanks, there are numerous liquid-based bacterial, parasitic, and fungal remedies. Researching these health concerns is imperative, so you know exactly what path to take with your aquarium-keeping.

Aquarium Keeping as an Art

With this basic understanding of tank setup and aquarium-keeping, you are on your way to being a successful aquarist. Not only will your aquarium teach you more about biology, but it will also teach you more about planning, responsibility, and creativity. Just as fish and people are dynamic, the possible aquarium habitats you can build are dynamic, intricate, and full of opportunity.

Lastly, aquarium-keeping will teach you more about the unique nature of each and every living creature. In one way or another, all fish have some level of personality. In taking care of these animals, you will learn more about the world around you and ultimately your role in it.

At the end of the day, your aquarium is what you make of it. You are the creator of this world, and the lives in this world depend on you. Aquarium-keeping is an art of science and creativity, and when you master this art, the world is what you make it.

Perhaps aquarium-keeping starts to pique your interest in fields, like marine biology. To learn more, check out these resources.

Hi, I’m a San Diego-based blogger who's passionate about marine biology, finance, and science communication. Having recently graduated from UC San Diego with a bachelor's in marine biology, I am now working on a certificate in science communication. Over the years, I’ve worked in laboratory research and science outreach at aquariums, zoos, and environmental research centers. When I’m not writing, you can find me home brewing, tide pooling, skydiving, playing DnD, or hanging out with my two adopted guinea pigs. Reach out to me anytime, and follow Sand Dollar Wallet!


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.