New Tank Syndrome, How To Overcome It

Setting up a new aquarium is exciting as well as interesting. However, some unexpected challenges may come and you may lose all the fish in your aquarium in a matter of two weeks.

One of the threats that could be awaiting fish in a brand-new aquarium is the new tank syndrome. Typically the first-timers suffer from the syndrome mentioned above in the early stages of their aquarium journey. 

If you don’t take preventative measures and don’t prepare the new aquarium properly, you will most likely encounter the new tank syndrome.

Sometimes, the new tank syndrome affects established tanks too! If you don’t take action, your fish may suffer weakness, illness, and even die.

With that, below, let’s try to understand what the new tank syndrome is and how to deal with it! After reading this article, hopefully, you will be able to solve such problems efficiently.

What Is The New Tank Syndrome

I assume most of you are familiar with the term ’nitrogen cycle’ in a fish tank. In a healthily established tank, a complete nitrogen cycle will occur. A new tank is not a properly cycled tank.

The new tank syndrome occurs when the nitrogen cycle is not established. In an aquarium ecosystem that is more or less balanced, the nitrogen cycle occurs as follows:

nitrogen cycle in fish tanks
  1. Fish waste, dead organisms, and leftover food break down, producing ammonium (NH4+) and ammonia (NH3).
  2. Beneficial bacteria in the tank – called nitrifying bacteria – consume ammonia and ammonium, producing nitrite (NO2-) as a result.
  3. The nitrite is then consumed by Nitrobacter microorganisms, which results in the conversion of nitrite to nitrate (NO3-).
  4. Nitrates are then removed from the tank as you change the water. Additionally, some aquarium plants consume nitrates as food. Read more on how to lower nitrates in aquariums.

Nitrates are significantly less toxic than nitrites and ammonia, but they can harm fish too in high concentrations. Though nitrates result from a nitrogen cycle, they are easier to manage, so a nitrogen cycle is desirable. 

If the nitrogen cycle is disrupted, the aquarium water’s acutely harmful substances will not be removed, and your fish will become intoxicated.

Why Is It Called ‘New Tank’ Syndrome?

Well, how does this fit into the concept of the “new” tank syndrome? In a new tank with clean water, there are too few nitrifying bacteria in the aquarium.

With that, the ammonium, ammonia, and nitrites produced by fish waste are not filtered from the water. As these substances build up, they increase the toxicity of the water for fish.

The New Tank Syndrome

So new tank syndrome basically represents the symptoms of toxicity build-up in the aquarium water. Aquarium water often becomes smelly, and cloudy because of excessive ammonia and nitrites, until bacteria colonies establish.

Usually, this happens in tanks that are about one to twenty days old, and maybe even longer than that since it takes a few weeks for enough bacteria to establish themselves to handle the waste produced by the fish.

How To Identify The New Tank Syndrome

To effectively spot and prevent the new tank syndrome, you should monitor the water quality for 6-12 weeks after you’ve built a new aquarium. And even to get early symptoms, make use of ammonia and nitrite test kits to keep track of the tank’s water condition.

In the early stages of the cycling process in a new tank, the ammonia level should be kept below one ppm, while nitrites should be below 1.5 ppm. As the cycling process matures, both should be nearly zero. As nitrifying bacteria colonies develop in the tank, ammonia, and nitrites will plummet down.

Aside from test kits, you may also keep an eye out for symptoms of the new tank syndrome in fish:

  • Staying at the surface longer than usual and gasping.
  • Moving the gills vigorously (rapid breathing.) 
  • Damaged gill membranes.

How To Prevent And Deal With The New Tank Syndrome

Here are some primary measures you could take to prevent the new tank syndrome. Though efforts are slightly different for an immature and existing aquarium, the basic principle is the same. Your intention is to remove toxicity from the aquarium water and relief your fish from stress.

Cycling The New Aquarium

Cycling The New Tank

The process to establish a nitrogen cycle from the beginning to mature stages is called ‘cycling’ in short. There is no alternative to cycling a new tank to overcome the common syndrome.

I have a detailed article on ‘Nitrogen Cycle in A Fish Tank – What It Is and How To Cycle A Fish Tank.’ You will get all the necessary information about the cycling process there. 

Here I am giving highlighted aspects of the cycling process.

Slow Cycling With Fish

With slow cycling, you cycle the new aquarium with the fish in the water. Generally, it’s recommended to start cycling with hardy fish that will better tolerate elevated ammonia and nitrite levels. Once their levels normalize, you may add more delicate fish to the tank.

Cycling With Fish

For slow cycling in freshwater tanks, fish species like Bettas and Guppies are commonly used. In saltwater tanks, you may use Damselfish.

It will take 1-3 months until a substantial population of nitrifying bacteria is established in your fish tank. Fortunately, you may make use of fishless cycling to bypass this problem.

Fishless Cycling

With fishless cycling, you keep your fish in the old tank – in the meantime, you should manually add ammonia to the new tank. Usually, 3-5 drops of ammonia per 10 gallons of water are added for fishless cycling. The addition of ammonia to the water will encourage the formation of healthy bacteria.

While adding ammonia to the tank, you should test the water for ammonia, nitrite, and nitrate daily. Initially, the ammonia levels will be high, while the latter two will be very low.

Fishless Cycling

Once you detect nitrite in the water, you may reduce the ammonia to 3 drops per day but continue to test the water.

Ultimately, your goal is to reduce the levels of ammonia and nitrites close to zero. Once you achieve this, your aquarium will have cycled, and you may safely move your fish.

Seeding The Aquarium

Another good option for cycling is to use bacteria from the old tank. This will noticeably boost the process of cycling. You may seed the tank both with and without fish.

Nitrifying bacteria usually find a home inside the tank filter. Have a look at the old aquarium’s filter media – those that are browned have bacteria cultures on them. You may simply drop the media into the new aquarium or use it in the new tank’s filter.

Seeding the Aquarium

Additionally, you may move plants, substrate, and water from the old tank to accelerate the process.

With that said, avoid seeding the new aquarium if the old tank is infested with aquatic parasites.

Adding Cycling Bacteria To The Tank

Finally, you may just purchase nitrifying bacteria off the shelf and add them to the water. This is the quickest way of cycling a new tank. Some brands claim that you may relocate the fish immediately after adding bacteria to the new tank!

Add Cycling Bacteria

However, you should wait for about a week just in case to let the bacteria settle in the filter and substrate.

New Tank Syndrome In Established Tank?

YES! As I already mentioned, it can also appear in an established tank. It happens if bacteria colonies present in the aquarium are destroyed or the amount of toxic substances is too much for bacteria to handle. Why can this happen? Let’s find the reasons. 

#1: Cleaning Is Too Thorough

Cleaning is good as a part of routine maintenance; however, too much cleaning is not. 

You need to be cautious about preserving bacteria while cleaning. For example, washing filter media under tap water can kill bacteria. Tap water contains chlorine, and therefore you should use old tank water for washing and save as much old tank water for reuse. 

More readHow to Clean Aquarium Filter Sponge (What You Must Know)

Don’t replace the filter media entirely; instead, change it partially. 

Moreover, it’s very possible that the cleaning is too thorough. Beneficial bacteria don’t live only inside the filter. They are present on every surface of your aquarium, including gravel, decor, glass, etc. 

Too thorough cleaning results losing bacteria

Never scrub the decorations, glass, etc., on the same day of changing filter media. Cleaning aquarium filters, substrate, rocks, plants, and changing water, all at a time may crush the cycle. 

Never use tap water directly into the aquarium; chlorine and chloramine will kill the bacteria. Make sure to use a de-chlorinator before putting it in your fish tank.

#2: Antibiotic Use

Another reason for developing new tank syndrome in a mature aquarium is antibiotic use. An antibiotic is the most common treatment when fish get sick and are affected by bacterial infection. 

Antibiotic use can destroy nitrifying bacteria

While you may have cleared the infection, however, in the meantime, antibiotics will also wipe out all the nitrifying bacteria populations from your filter, substrate, decors, and water column. 

Therefore, it’s recommended to treat any diseased fish in a separate quarantine tank.  

#3: Overstocking and Overfeeding

Overfeeding and overstocking mean more waste to handle for the bacterial colonies. Excessive trash inhibits bacteria growth. In addition, bacteria also need high oxygen levels to thrive, which they won’t receive if the tank is overcrowded with fish.  

Excessive waste hinders bacteria growth

Therefore, limit your feeding and stock in the right proportion to avoid such occurrences. 

How to Fix New Tank Syndrome

Once the cycling is retarded, you will observe new tank syndrome in the old tank. In that case, take timely action to save your fish’s life.

How to fix new tank syndrome

#01: Check the Filter

First, check if the filter is working correctly. If it is, then check the last time you cleaned the filter. A clogged filter will not be able to remove the waste from the aquarium water. 

If you think it’s time to clean the filter, then do it first. If the issue was related to the filter, the problem would be resolved after cleaning or replacing the clogged media. 

#02: Perform Water Changes

After checking the filter, your first task is to perform a water test. 

The water test result will guide you on how much water you need to change. Ideally, the ammonia and nitrite levels should be zero. Properly prepare the new water before using it in your aquarium.  

As of now, you have to re-establish the complete nitrogen cycle to achieve it. By this time, ensure the ammonia and nitrite levels do not exceed 1 and 1.5 ppm, respectively. 

#03: Clean The Substrate

Food leftovers and other wastes get trapped inside the substrate and decomposed to form ammonia. If the ammonia level increases, the established biological cycle may not be adequate to convert all the toxicity. 

In such a case, only water changes may not be sufficient. Therefore, I will suggest planning to clean the aquarium substrate thoroughly to eliminate entrapped ammonia.

Use a stirrer and gravel vacuum to perform the cleaning task effectively. 

#04: Lower The Fish Density & Feeding

If you observe fish suffering from increased toxicity symptoms, you can transfer some fish to another tank or to a quarantine tank if possible. However, it is tough to re-establish a nitrogen cycle in an overstocked tank. 

More Read:

Secondly, stop feeding or provide less food than usual for a few days. If the fish are not active because of the New Tank Syndrome, and food you put in will pile up to waste. 

#05: Add Bacteria

Lastly, I suggest adding nitrifying bacteria to speed up the recovery process. The easiest way is to use cycle products to enhance bacteria growth. 

Two More Quick New Tank Syndrome Cure

Your fish may be suffering and struggling to breathe because of all the pollutants & toxic matter present in your aquarium. However, there are two things you can do to alleviate some of the misery. 

  • First, increase the oxygen level by using an air pump and an air stone. That will help not only your fish but also bacteria. 
  • You can also add some aquarium tonic salt as a quick relief. This will detoxify the nitrite in your tank. 

Final Words

The new tank syndrome may occur in already established aquariums – most often happens after a thorough cleaning, using antibiotics, or in an improperly maintained aquarium. 

These disrupt the established bacteria colonies, which may result in ammonia and nitrite spikes.

No matter what you do, make sure to regularly test the water in the tank and keep an eye on your fish. If you see any breathing difficulties or gill damage symptoms, you are most likely dealing with the new tank syndrome.

I would like to hear about your experience with this issue, if any. Besides, your suggestion and comment are highly appreciated. 

Sujit Modak

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