What Should Your Saltwater Aquarium Water’s Test Results Look Like?
The Deadliness of a Sterile Tank
The most difficult task for new aquarists to encounter is in starting and finishing the nitrogen cycle in their aquariums. Interpreting the test results however, can be a challenge on its own. Sometimes, even the most experienced of aquarists still encounter difficulties stabilizing their aquarium water’s parameters, while plenty others more never even manage to complete the nitrogen cycle. It is said that it takes at least one year for an aquarium to naturally mature enough to be able to sustain marine life. This can be done with the addition of live rock and plants and corals, as well as filter media from another, mature tank, but, realistically speaking, who wants to wait all year? Luckily, these days, all it takes is to add live nitrifying bacteria into the tank to establish the colonies necessary for the nitrogen cycle to begin and to continue running on its own, and you’ll be well on your way to a full-cycled tank (that means completing all the phases of the nitrogen cycle — and not “cycle” as in for the filter to cycle all the water in your tank, which I was initially led to believe!) in as little as 12 days (based on my experience).
Little do most people know that a so-called “sterile” tank (i.e. free from bacterial colonies) is unfit to sustain aquatic life in the long-term, and can even be toxic for its inhabitants. Without any beneficial bacteria around to consume excess decaying matter, the animals are essentially sitting in raw sewage. Think about that for a second and consider why most people fail as aquarists — it’s because they think that keeping aquatic life is simply a matter of adding water into a tank. In reality, it’s probably the most involved type of pet. Unlike the average pet, you also have the additional responsibility of replicating the conditions of the ocean, and maintaining those conditions, in your home! In a sense, it is, in fact, creating their own world for them.
Below I walk you through the process of the nitrogen cycle for saltwater aquariums and show you, visually, what to expect and what to watch out for when reading test results, aside from what ideal and toxic parameters’ test results look like.
Test Results
Saltwater Aquarium
As we take a look at the images above, scrolling from the topmost left corner to the right, and working according to the same direction for each row all the way down, notice how there is a decrease in ammonia, nitrite, and nitrate levels, with the passing days. The first image shows the aquarium water on the first day, prior to the addition of any beneficial bacteria or livestock, while the second image shows the same aquarium water’s ammonia levels rising along with the nitrite and nitrate levels. This is a result of a deficiency in beneficial bacteria, and thus, we will need to supplement the aquarium with beneficial bacteria. In the third image (first row, third column from the left), we see a drastic decrease in ammonia levels. This tells us that the nitrifying bacteria successfully established colonies within the aquarium that were large enough to consume all of the ammonia. If we move along further, comparing the 7th and the 8th images together, now we see the decrease in nitrite to yield a zero reading. The 9th image however, shows a sudden increase in nitrite. This can be caused by the addition of food or some other form of decaying matter. I purposely left extra animal waste behind, to continue feeding the nitrifying bacteria. Beneficial bacteria also need a food source to replicate. In the 13th picture, we see that both the ammonia and nitrite levels yield a reading of zero, but the nitrates are still within the 5.0 ppm to 10 ppm range. Nitrates are the lest of the concerns when compared to ammonia and nitrite levels, so this is the point where you can start to relax, knowing that the nitrogen cycle is nearing completion.
The last image shows a zero reading for ammonia and nitrite. This was taken 28 days after beginning the nitrogen cycle within the saltwater tank. The test shows that nitrate is still present — around 10 ppm — but at this level, it is safe to retain some level of nitrite to feed the bacteria.
(Note: I plan to write a separate article for other water tests to perform, such as Calcium and Phosphate.)
Atlantic Ocean Water
As we see in the images above, the Atlantic Ocean is able to take care of itself and its marine life, with test results showing a perfect pH reading between 8.0 and 8.2 and zero readings for ammonia, nitrite, and nitrate. These are the most ideal conditions to support marine life, and the goal is for your aquarium to resemble these readings as closely as possible, and to be able to maintain them.
Imagitarium Pacific Ocean Water
The Imagitarium Pacific Ocean Water on the other hand, also shows perfect, zero readings for ammonia, nitrite, and nitrate, and a pH rating of 8.4. This is the target pH level for maintaining a healthy saltwater reef aquarium.
Fritz Aquatics FritzZyme 9 Nitrifying Bacteria
Moving on to the FritzZyme 9 bottle of nitrifying bacteria, we see an ammonia reading of at least 8.0 ppm, with zero readings for both nitrite and nitrate. This is expected, as ammonia is purposely added into the bottles of nitrifying bacteria, to serve as their food source to keep them alive. Take note however, that all it takes is too hot or cold of an ambient storage temperature for the bottled bacteria to be killed. You have better chances of receiving live bacteria by walking into a brick and mortar store to make the purchase, rather than on Amazon; or better yet, through buying directly from the manufacturer’s website (wherein they take care to ship their products with cold packs, depending on the time of the year).
Before adding any nitrifying bacteria to the water, test the solution first to be certain that only ammonia is present, and not nitrite nor nitrate (this means that you’ll need enough of the bacterial solution to dose your aquarium with, even if you subtract some for testing). One unfortunate aquarist posted a review on Amazon, stating that the bottle of nitrifying bacteria that he purchased, contained high levels of nitrite instead, which became responsible for the death of his animals, only finding out when it was too late. It is good practice to test any bacterial solution or water prior to adding it into your aquarium, and one that can spare the lives of your animals.
Quarantine Tank
Here is a perfect example of the kinds of readings that you will see if you leave uneaten food for many hours inside a temporary tank (i.e. one with no filters nor beneficial bacteria). In this case, I made the mistake of leaving too much raw shrimp for my white speckled hermit crab when I transferred it to the temporary tank for quarantine (so as to prevent its exposure to high levels of nitrite), but when I woke up the following morning and saw it sluggish and unhappy next to a decaying piece of shrimp, I tested the water and became alarmed at the test results. At that point I decided that it was much better for my crab to tolerate the rising nitrite levels in the aquarium, rather than the ammonia. Ammonia is far more toxic than nitrite is, to invertebrates. The first picture shows the parameters in the tank on the previous evening, with zero food, prior to changing the tank’s water, while the second and third pictures show the water’s test results the following day, after many hours have elapsed with the decaying shrimp polluting the water, and also after I had changed the water before immersing my hermit crab in it.
That’s all for now! I’ll update this page as I progress along!
Last update: March 2, 2022 at 18:44 ET