How to Maintain a Healthy Home Aquarium

September 29, 2020 Phil Overton

If you’re looking to purchase some new fish for your home—or you already have a tank and aren’t sure if you’re doing everything you need to keep the water clean and environmentally balanced—you might be wondering How do I properly maintain a healthy at-home aquarium?

A flock of fish: pearl gourami and bloody tetras

It’s important to set up a tank that not only looks beautiful but is also optimized to maintain life and keep a proper balance where beneficial bacteria (and your fish!) can flourish. Changes in pH, high nitrate levels, and improper temperatures, can all determine whether the tank will remain healthy and your fish will thrive. Because of this, it’s important to understand how all these factors tie into properly maintaining your tank.

This article provides information about the major steps you can make to ensure a healthy life-support system for your fish, including what signs might indicate something might be off-balance and how to rectify the issue before it becomes problematic.

“Cycling” your Tank

It’s important to give your new at-home aquarium enough time to “cycle.” This is a natural process whereby, after a few hardy fish are added (or food or liquid bacteria to a fishless tank), beneficial bacteria are able to grow and proliferate to help break down the wastes your fish will produce. These bacteria nearly eliminate ammonia and nitrite in the tank, which are harmful to fish.

Perform routine water changes

Once the cycle is complete (this step can take several weeks) and all the harmful ammonia and nitrite are converted by the beneficial bacteria to less-toxic nitrate, you can add more fish. Next, and depending on your fish load (how many fish you have in the tank), you will want to change out about 25­–30% of the water in the tank as necessary (depending on your level of nitrates).

Typically, freshwater tanks should be maintained at under 40 ppm (parts per million) nitrate, and in saltwater tanks, under 10 ppm. Just keep in mind this can vary depending on the species of fish you are keeping, so be sure to change the water accordingly; the frequency of these water changes can range from weekly to monthly. For example, if you don’t have many fish and they aren’t big eaters (therefore producing less waste), you can likely go a bit longer, and you can also perform less-frequent water changes if you’re using some of the higher-end filtration media that are able to complete the nitrogen cycle by changing nitrates to nitrogen gas.

The idea with water changes is to only swap out about a quarter of the older, higher-nitrate water so that you are diluting the nitrates, but be careful to not disrupt the tank’s balance by adding water that will adjust the temperature or pH too drastically. The water you’re using to refill your tank should be similar to the tank’s water in pH and should not have chlorine, which will kill the beneficial bacteria that have established in your aquarium. If you need to modify the hardness or eliminate chlorine, you can adapt the water appropriately by conditioning the water prior to adding it.

Test water parameters regularly

One of the biggest indicators that you might start experiencing issues with your at-home aquarium is, if one of the factors listed below is falling outside the range that your particular aquarium requires. Keep in mind that these factors will vary based on the type of tank and fish you have. Some fish are able to thrive in higher-pH environments while other are extremely sensitive to changes, so try to keep the best balance you can depending on your pets’ specific needs.

That being said, these are the typical parameters you should be checking on a regular basis (at least once per month) for fresh water aquariums to ensure your tank is functioning optimally, which can be determined by using an aquarium testing kit:


When your fish eat food and produce waste, or uneaten food and plant matter begin to break down, this creates ammonia. It can damage the fish’s gills and affect the way they are able to use oxygen, making the fish sick and ultimately causing death.

betta fish Aquarian fish swims in aquarium water

Ammonia is, however, a natural part of the nitrogen cycle, which is why it’s important to let any tank cycle through these phases (ammonia to nitrite, nitrite to nitrate) before adding more fish. Still, checking for ammonia on a regular basis is an important part of maintaining your at-home aquarium because even after the nitrogen cycle has had time to complete itself, you can see potential spike in ammonia.

Spikes in ammonia are often caused by:

  • overfeeding the fish or overloading the tank (where biodegradable waste is at too high a level for the beneficial bacteria to convert)
  • inefficient surface area (that can’t build enough beneficial bacteria to remove enough waste)

Aquarists generally say it’s best to keep ammonia below 0.02 ppm, which should ideally be non-detectable in the home test kits

If your ammonia levels are creeping up, try to pinpoint why (Are you feeding too often? Is there a lot of decaying plant material or dead fish? etc.) and adjust the levels accordingly. Just keep in mind this can indicate an emergency where you might need to add ammonia removers or beneficial bacteria or change a larger percentage of water to get the ammonia down. Sometimes ammonia rise occurs when there is chlorine present in the replacement water. Chlorine kills beneficial bacteria therefore testing your water source for chlorine is extremely helpful.  


Since denitrifying bacteria converts ammonia to nitrite, you will typically see a nitrite spike after a spike in ammonia. Too-high nitrite levels in your aquarium mean your fish will have trouble absorbing oxygen into their bloodstream.

Since the presence of nitrites indicate that the nitrogen cycle in your tank is in its second phase, many of the same corrections as treating high ammonia—like changing out a portion of the water or feeding the fish less frequently—apply. Aim for 0.01 ppm of nitrite or less but also keep in mind that nitrites will typically be nondetectable in a well-balanced aquarium.


Not as toxic (by far) as ammonia and nitrite, the presence of nitrates is an indication that the final phases of the nitrogen cycle are occurring. Because nitrates aren’t as toxic to your fish as ammonia or nitrites, try to keep levels below 5 to 10 ppm (also keep in mind that freshwater fish can be more tolerant of nitrates while saltwater fish are not).

Nitrates are typically mitigated to a certain degree with regular water changes. Keep in mind, Nitrates may be present in the water you are using to refill your tank. Some biofiltration media will remove nitrates, and there are also aquarium plants or beneficial bacteria that can use the nitrates in your tank and lower the levels, too, but these might be longer term solutions and might take a bit of time to build up the necessary environments for a substantial change in number.


Different water sources have different pH values, and furthermore, your tank’s pH can change as your fish eat and create waste and plants and dead fish decay. Test and adjust pH once a month, as variations in pH can affect your fish’s health.

Most pH level recommendations will be to keep levels neutral (between 6.5 and 7.5) but this will very according to the types of fish you keep.

Clean all surfaces

The last step to maintaining your fish tank is to regularly clean the surfaces in and around the tank. This should also be done once per month, but some aquarists will recommend doing it on the opposite weeks of your scheduled water changes so you don’t remove too much beneficial bacteria at once.

You’ll want to clean the sides of your tank, vacuum waste out of the gravel, and remove and rinse any filtration devices you’re using. Algae is a sign that your tank is healthy and properly balanced. Remove what you like, but you might want to leave a little in the tank, especially for fish that eat it. Another point to keep in mind is that Nitrate is a fertilizer for plants and algae. Keep an eye on the algae and if you see a lot of it or the water is turning green, chances are your tank’s nitrates level are high and it could use a water change, which should help to clear it up.

Cleaning of gravel in a freshwater aquarium. Pseudo-sea style of design

You do want to vacuum out and remove all the settled debris from the gravel, which will decay and break down into ammonia. Alternatively, you do not want to clean your filtration media too often or thoroughly to prevent excessive loss of beneficial bacteria. Depending on the filtration media you are using, some will need cleaning or replacing more than others, but the manufacturer should have these types of instructions on the box. Some high end biofilter medias do not need cleaning as there is ample surface area and clogging is not a concern.

Using MarinePure® biofiltration for optimal aquarium health

MarinePure® biofilter media is a man-made porous ceramic structure that has a large amount of surface area for beneficial bacteria to grow. With open-flow pores, water moves easily throughout the media, allowing the nitrogen components to encounter the bacteria and allows all parts of the nitrogen cycle to take place (easily eliminating ammonia and nitrite and reducing nitrate).

This allows for fewer water changes and less tank maintenance. MarinePure® also comes in different shapes and sizes making it easier to use it in any type of aquariums and set up.

Learn more about how MarinePure® can be used in your at-home aquarium and all the benefits of this biofiltration media’s unique and patented design.

If you have any questions about how to access MarinePure® Bio-Filter Media or incorporate into your new or current tank, feel free to reach out to us. We’d love to help walk you through how to use this bio-filter media for a cleaner, easier-to-manage fish tank.


Leave a Reply

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


Contact us to learn more about how MarinePure and BioVast can help your aquarium and aquaculture environments!


P.O. Box 600
66 River Rock Dr.
Buffalo, NY 14207
USA or

(716) 549-6600

Leyda Vazquez
Business Development Manager
(716) 549-6600 x264

Paul Pustulka
General Manager