Many of us purchase new fish at our local pet store and then enthusiastically rush home, where we tend to make the most common mistake as aquarium enthusiasts. By leaving the bag afloat in our aquarium for a short period of time in order for the temperature to adjust. And, in some cases, we may even open the bag up and scoop a little bit of our aquarium’s water into the bag. Then, we simply dump the bag of fish, water and all, into our aquarium.
Why Acclimate New Fish?
Improper acclimation often leads to the spread of disease, increased stress, and loss of life among your newly purchased pet fish and your aquarium’s inhabitants. Understanding how to acclimate new fish safely using the drip acclimation process can significantly mitigate these risks compared to any other method.
More often than not, our local municipal water source delivers similar water parameters throughout the city. But, there are still many different factors that lead to our home aquarium’s water parameters differing from our local pet stores. Such as residential zones which source their water from underground wells or a second treatment plant in a larger city.
Additionally, a newly installed aquarium may still be in the process of establishing its water parameters, and an established aquarium with infrequent water changes will likely have a lower pH since the nitrification process continually decreases pH levels. Various elements, including rocks and driftwood, can also cause pH and dH levels to fluctuate.
pH Shock in Fish
According to recent studies, many species of fish are particularly vulnerable to pH shock, which can cause abrupt mortality. While some might endure chronic, non-lethal effects and others might experience minimal or no symptoms.
The above-mentioned study had acclimated several groups of fish with a pH value of 8. To evaluate the impact of rapid pH fluctuations, four testing tanks were set up with pH values of 6, 7, 9, and 10 (Tanks 1, 2, 3, and 4). The following effects and symptoms were noted during this study:
- Tank 4 experienced a 100% mortality rate within 15 minutes, the fish attempted to jump out of the tank while secreting mucus during this process.
- Tank 3 experienced a 40% mortality rate within 10 hours, two of those fish lost equilibrium within the first 10 minutes. All fish showed signs of abnormalities for the first 3 hours before their behavior returned back to normal.
- Tank 2 showed mild distress with a zero mortality rate during a 10-day observation period.
- Tank 1 experienced a 20% mortality rate within the first 5 hours. Slow movement and loss of equilibrium were the most common symptom.
Temperature Shock in Fish
Studies have shown that a fish exposed to as little as a 1°C cold shock resulted in a large increase in plasma cortisol before returning to normal after 24 hours. Symptoms of cold shock include stress, comatose, failure of osmotic regulation, weakened immune systems, gill tissue damage, abnormal swimming behavior, lethargy, loss of equilibrium, and even death.
Fish have nociceptors to sense heat, which is equivalent to our pain receptors. Symptoms of hot water shock include tissue damage, abnormal swimming behavior, jumping out of the water, collisions, loss of equilibrium, gasping, and death.
With that being said, some species will be much more sensitive to sudden temperature changes than other species of fish. Fish are highly adaptable to changes in water temperature throughout a slow and steady increase or decrease.
Depending on the degree of the temperature change, a recently acquired pet fish that has been acclimated to the aquarium at your neighborhood pet shop and then promptly released into your home aquarium may exhibit some of the symptoms listed above.
How to Acclimate New Fish
For any fish being transferred to a new tank with differing water parameters, drip acclimation is strongly advised. Fish do not tolerate abrupt changes in water parameters at all, and even if they do survive, these conditions can cause serious long-term health impacts that may very well shorten their life span.
It is also strongly advised to use the drip acclimation method if you are purchasing fish online or if the fish has been in transit for more than a day. Due to the absence of a working biological nitrogen cycle, ammonia and nitrites will build up and effectively lower the pH of the water, and the temperature will significantly fluctuate during cold or hot days.
However, the floating method will effectively work in some situations if the water parameters at your local pet store are similar to those in your aquarium at home. Ask the staff at your local pet store for their water parameters if you are unsure.
Using a pH and GH test kit, check the water parameters in your aquarium. You should be okay to use this method if your aquarium’s pH is within 0.5, the temperature is within 2ºF, and GH is within 2 dGH (35 ppm) of your local pet store’s water parameters.
In order to lessen any potential stress that any new or existing occupants may experience during this process, turn off the lights in your aquarium.
Roll down the sides of the bag several times to create a large air pocket sleeve after opening it. As a result, you will be able to place the bag inside the aquarium and it will float with ease.
Scoop 200 – 250 ml of your aquarium’s water into the bag using a clean cup, then repeat this process in 15 minutes.
Next, empty half of the water from the bag into a sink and add 200 – 250 ml of water from the aquarium at least twice more, each time waiting 15 minutes between additions.
You can add the fish to the aquarium after this process is finished. Avoid adding water from your local pet store to your aquarium because it is likely contaminated with parasites, medications, etc.
Before turning the light back on, wait at least an hour or two to give your aquarium’s inhabitants a chance to establish territories and hiding places.
Fish Drip Acclimation
When it comes to acclimating fish, the drip acclimation technique is by far the safest. They won’t experience shock from sudden changes in water conditions if water is gradually siphoned into a bag or bucket at a slow and steady rate.
It will only become more simple when you gather all of the supplies and complete the drip acclimatization process once, and it will likely become your go-to technique each time you need to acclimate fish.
During the fish drip acclimation process, water from your aquarium is gradually siphoned from a PVC tube into a bucket or bag of recently purchased fish. The required equipment is as follows:
- An Aquarium friendly drip line such as a 3/16 inch PVC tube or aquarium airline tube.
- A 5-gallon or smaller bucket that is capable of holding your bagged fish.
- A clip to fasten the PVC drip line and bagged fish to the bucket’s handle and the tank’s edge, respectively. It will prevent the bagged fish from leaking into the bucket and the PVC drip line from coming loose from the aquarium.
- Flow control valve (optional). Instead of tying a knot in the tube, this can be used to change the drip’s speed.
- Fish net.
To maintain the flow of water that will be siphoned using the PVC tube from your aquarium, the bucket must be positioned beneath the tank.
If you don’t have a flow control valve, skip this step. If you’re going to use one, you’ll need to cut two pieces of 3/16-inch PVC to the appropriate length. The combined length of the two parts must be long enough to reach both the interior of your aquarium and the bottom of the bucket. The PVC tubing should easily slip onto the flow control valve when you are connecting it to both pieces of PVC tubing.
Simply tie a knot in the middle of the 3/16-inch PVC tubing if you don’t have a control valve, but don’t tighten it just yet. You’ll still need to be able to start the siphon, the knot should be rather slack.
In order to prevent the bag from toppling over, place the bagged fish into the bucket with one side of the bag secured to the edge of the bucket using the clip or you can pour the water and fish into the bucket.
Once the PVC tube is in the tank and the line is fastened to the edge, you may start the siphoning process. Use the bucket to collect the water while you tighten the knot or adjust your flow control valve before inserting the PVC tubing into the bag.
If the water parameters at your local pet store are rather close to those of yours, you can slightly raise the drip rate from the recommended level of about one drip per second. Now that the drip rate is under control, insert the drip line into the bag. Halfway through the drip process, empty out half of the water and then continue the drip process.
After the drip acclimation process is complete, gather the fish using the fish net and gently place them in the tank with the lights turned off. For the first couple of hours, keep the lights off to give your new fish a chance to hide, which will help with reducing stress levels and discourage aggressive fish from fighting over territory.
Note: Aquarium water from your pet store should never be dumped into your home aquarium since it is frequently contaminated with pathogens, parasites, and medications.
How Long to Drip Acclimate Fish For
Acclimating new fish to an established aquarium using the fish drip acclimation method may take between one and four hours. It would be advised to acclimate new fish for 2 – 4 hours if your water’s pH or temperature is significantly different from your local pet store (with a variance of more than 1 pH or 2º Fahrenheit).
If your water’s pH and temperature are similar to or lower than 1 and 2 degrees Fahrenheit, 1 – 2 hours of drip acclimation will be sufficient. Water will cool when there is no source of heat, so you will also need to think about how long your new fish will be traveling.
We all lead incredibly busy lives, so it makes sense why most people opt to ignore the drip acclimation approach. However, it is best to stick with this technique for the sake of both your budget and your fish’s health.
Quarantining New Arrivals
It is strongly advised to have a small spare tank set up specifically for acclimating and quarantining new species of fish while you are buying and introducing new fish to your home aquarium.
The majority of pathogens and parasites that affect fish have an incubation period of 30 days or less. Knowing this, it is preferable to quarantine all newly acquired fish for 30 days, allowing for careful observation to detect any symptoms. Newly introduced fish have the potential to infect your aquarium’s residents swiftly, frequently resulting in devastating losses of life.
After the 30-day quarantine is through, you may anticipate that your fish will have a far better chance of living a healthy and long life.
Start providing the right care and treatment for any fish who exhibit symptoms of poor health. Once the 30-day quarantine is complete, it is safe to assume that your fish will have a much higher chance to live a healthy and long life.
Maintaining a smaller secondary filtration system on your primary aquarium that can be detached and connected to a spare tank is a great alternative for those who do not continue to run quarantine tanks.
This avoids “new tank syndrome” and maintains the nitrogen cycle. After the quarantine tank is no longer in use, discard the filter to prevent contaminants from entering the main tank with any pathogens it may have acquired, and reconnect it to the primary aquarium after a thorough cleaning and installing a new filter.
Aadil Yahiya, Saeed Mohammed, and Jithu Paul Jacob. Acceptance of Thermal and pH Shock on Red Belly Pacu (Piaractus brachypomus) in Adverse Rapid Environmental Conditions. 2020
M. Donaldson, S. Cooke, D. Patterson, and J. Macdonald. Cold shock and fish. 2008
Jonatan Nilsson, Lene Moltumyr, Angelico Madaro, Tore Sigmund Kristiansen, Siri Kristine Gasnes, Ceceilie Marie Mejdell, Kristine Gismervik, and Lars Helge Stien. Veterinary and Animal Science. 2019