How to acclimate your fish to a new aquarium

When it comes to aquariums, how you add new fish to your tank is an important factor to their safety and well being. Follow these tips when acclimatizing fish to your aquarium.

When you are stocking your aquarium for the first time, you may want to take the time to think about the order in which you add your fish – especially if you are cultivating multiple species. Some fish are more aggressive than others, so you might need to add them to the tank first so they can establish their territory. Not only do you need to think about the order in which you add fish to your tank, however – you also need to think about HOW you add them to the tank. Proper acclimation is essential for the health and safety of your aquarium fish.

Why Do You Have to Acclimate Fish Slowly?

Many novice aquarium hobbyists make the mistake of bringing their fish home from the pet store and simply emptying the bag into their tank. Then, they are surprised when their new fish die after just a few hours in the new tank. What these hobbyists do not realize is that the conditions in the pet store tanks could be different from the conditions in their tank at home. By throwing the fish into a new environment all at once, they are shocking the fish and causing them to become stressed and die. Acclimating new fish slowly helps the fish get used to differences in water temperature and water conditions before they are released into the tank. If you want to make sure that your new fish do not die right away, you need to learn how to acclimate them properly.

Methods for Acclimation

There are several different methods that aquarium hobbyists use to acclimate new fish to their tanks. The three most common methods are the floating bag method, the bucket method, and the drip method. The floating bag method is just what it sounds like – you take the bag that you brought your new fish home in and float it in the tank in order to give your fish time to acclimate to the temperature in your tank. You will also need to add small amounts of tank water to the bag over a period of time to get your fish used to any differences in water chemistry. The bucket method involves placing your fish (along with the water from the bag) in a bucket to which you add small amounts of tank water over a period of time. The drip method is by far the slowest method for acclimation, but that is also what makes it the best choice in many cases.

The Drip Method of Acclimation

To utilize the drip method of acclimation for your new fish, you should still start out by floating the bag containing your fish in the tank for at least 15 minutes – this will help to make sure that the temperature in the bag evens out to match the temperature in your tank. After the temperature acclimation period you can empty the bag into a clean bucket to begin drip acclimation. Start by tying a few loose knots in a length of aquarium airline tubing then place one end of the tubing into the aquarium and use a clip to hold it in place. Next, create a siphon by sucking on the other end of the tube until the water starts to flow through it. Then, position the end of the tubing over the bucket and hold it in place with a clip.

Start out the acclimation process with the water flowing through the tube at a rate of 2 to 4 drips per second. You can adjust the flow rate by tightening or loosening the knots in the airline tubing. Wait until the water volume in the bucket doubles, then discard half of it and start the process again. Once the volume of water in the bucket doubles again it is safe to say that your fish have been acclimated properly. At this point you can use a mesh net to catch the fish and then transfer them to the tank.

The process of acclimating new fish to the conditions in your aquarium can be a time-consuming process but it is necessary. If you rush the process you might end up putting the new fish in your tank before they are used to the new tank conditions and, as a result, they could become stressed and die. Do yourself and your fish a favor by acclimating your fish properly.

How to acclimate your fish to a new aquarium

While it is exciting to purchase fish at the pet store so that you can bring them home and add them to your home aquarium, the sad part is that lots of fish die shortly after being introduced to the home habitat.

Lots of pet stores get blamed for selling fish in poor health; however, the reality is that the untimely passing is more often due to budding home aquarists not knowing how to properly acclimate aquarium fish to their home aquarium habitat.

It’s a common misconception that all you need to do is float the bag in the tank for a few minutes and then dump the fish into the water. However, in the following guide, we’ll take a look at how to correctly acclimatize your fish to their new home and ensure that your fish live long and healthy lives.

The Proper Way to Acclimate Fish

How to acclimate your fish to a new aquarium

Step 1

To avoid shocking your new pets when you bring them home, turn down the lights. You should then take the rubber band off the bag. Place the bag in the tank so that it floats on top of the water.

Thereafter roll open the top of the bag four or five times to create rings of air around the bag that will cause it to float. However, in the event that the bag is unstable, roll it down a few more times to create more stability.

Step 2

Acclimating is not an easy process; however, it is a slow and steady one. So to get started, dip half a cup of the tank water and add it to the bag. Wait 15 minutes and repeat this step.

This slow process will allow the fish to acclimatize to the change in water pH and temperature as well as oxygen content, new nutrient levels, sounds, salinity, and lighting.

The best chance that your fish have of survival is a slow and careful process. It will not protect your fish from any diseases or parasites the new ones are carrying, though. It’s also important to be aware that the quality changes in water is only one of the aspects of acclimatizing your fish, and new fish’s life depends on you following the proper process.

Step 3

In order to ensure that the water quality is right your fish, you should test the nitrate, hardness, nitrite, ammonia, pH, alkalinity, and temperature on a regular basis. When on the water tests have been done, then only should you consider adding your fish to your aquarium.

This is because new fish added into the aquarium increases the bio load on the filter system, so that said only a few new fish should be added into the tank at a time.

Ultimately, this will allow beneficial to accumulate enough in the biofilter and eradicate to dedicate the ammonia waste the new fish create before it starts to build up to toxic levels. Placing too many fish at once can overload the biofilter and cause fish loss due to ammonia increases.

You need to test the pH while the temperature is equalizing in order to avoid pH shock, so the pH of the water in the bag must be tested against the pH of the water in your fish tank at home. More often than not, for the short trip of an hour or less from the pet shop to your home, there will be a slight change in the water quality in the transported bag.

But on longer trips, such as when fish are shipped from the breeding farm, and then distributed into the pet shop, the fish could remain in the bag for approximately 2 hours and up to a maximum of a few days.

In cases such as these, the pH of the water tends to drop due to the fish’s respiration, and the ammonia levels in the water will increase.

Step 4

How to acclimate your fish to a new aquarium

Once the temperature and pH of the water in the bag is the same or similar to the water in the tank, remove the fish from the tank and net them. Carefully add the fish to the aquarium, ensuring that their fins don’t get caught in the net’s mesh.

Instead of pouring the water from the bag into the tank, you should get rid of it, and in the event that the water level inside your tank decreases, you should fill it with dechlorinated water.

Be sure to keep a close eye on your fish to ensure that they’re not bullied by the older fish. Feed the fish a small amount of food at this time so that the old fish are busy and less likely to bother the new ones. It’s always better to place new fish into quarantine tanks for between 2-4 weeks before adding them to the main aquarium.

Avoiding Problems During Acclimation

One of the predominant reasons why fish die after adding them to a home aquarium is pH shock. pH differences may seem insignificant to you but can be lethal to fish. In fact, a small or minute difference of 0.5 can send your fish into pH shock. Ultimately, they may or may not recover from this depending on the severity of the difference in the pH levels. The greater the difference, the more likely they are to die.

So do your homework on the different levels of pH for different species. It’s also important to remember that the pH in the water will gradually drop due to acids produced by the fish’s metabolism, so perform water changes on a regular basis to keep pH levels more stable and to restore the alkalinity in the water.

The goal to bear in mind is that you are trying to give your fish the best possible chance of survival in your home. The water in the fish bag will drop in pH and increase in ammonia during the transportation stage. So making the adjustment to different water quality less stressful as possible for your fish will help keep them healthy and alive.

Freshwater Fish

When it comes to freshwater fish, add a cup of water from your aquarium to the acclimation container.

The fish should acclimate for 10 minutes before repeating this step twice. Thereafter, the fish can be netted and added to the home aquarium.

Salt Water Fish

When it comes to acclimating saltwater fish, it is highly commended that you use drip acclimation. You can purchase a drip that is made specifically for this purpose. Ultimately, it tests the salinity of the water in the acclimation chamber and the salinity of the water in the home aquarium.


You may have had pet fish die in the past due to incorrectly acclimating them or perhaps you didn’t know you were even doing something wrong.

However, now that you are equipped and armed with the appropriate methods of acclimating fish, you can look forward to having an aquarium filled with happy and healthy fish.

After setting up your new aquarium and going through the tedious process of waiting for the tank to cycle, it can be very tempting to snag some pretty fish at the aquarium store and release them quickly to liven things up. Unfortunately, this can lead to significant problems: if you impulse buy and don’t acclimate, your new fish might not live a long and happy life.

So how do you make sure your new pets make it through the first few hours in their new home? Acclimation is key. We’ll tell you all about it below.

Why is Acclimation Important?

Stability is a very important keyword in fishkeeping and the reason you need to acclimate any new additions before introducing them into your tank.

Fish and invertebrates don’t respond well to sudden changes in water values and temperature at all. These swings stress them out and can easily lead to shock or even death. So as tempting as it might be to release new fish right away and see them swim freely in their new environment (we know the feeling!), you’ll have to be patient for a little longer. Spending a little more time in their bag or a bucket doesn’t hurt the fish and is much better than the so-called ‘plop ‘n drop’ method.

Plan, Plan, Plan

One part of the acclimation process that aquarists tend to forget is planning. It’s not just about giving the fish time to get used to the water values in your aquarium: you’ll also have to make sure those water values are actually in order. This is why, as frustrating it might be to avoid impulse buying your ‘dream fish’ at the aquarium store, you should always be prepared.

There are a few factors that you should keep in mind when getting ready for the arrival of new fish. First off, know when you’re going to buy or receive your stock. If you’ve ordered online, make absolutely sure that you will be home when the package arrives. Research beforehand so you know the desired water values for the species you’re interested in and make sure your aquarium is in the acceptable range.

The day before your purchase or the arrival of your new fish, do a water change to remove any excess nitrates. You don’t want to have to do this after their arrival, as you’ll want to leave them alone as much as possible to prevent stress. Lastly, the day of your purchase, perform one last water test to make absolutely sure your aquarium water is safe.

The Acclimation Process

Now that you’ve got everything set and ready to go, you’re ready to head out and get your fish. Yay! Try to make transport as stress-free as possible by using an insulated box to prevent temperature swings and keeping things dark.


Alright! You’ve got your new fish or inverts and have arrived at your home. It’s time to start the acclimation process, and the way to do so is by comparing the temperature in the bag to that of your tank. More than a five degree difference? Get the temperatures matched before moving on to drip acclimating. You can do so by floating the bag in your tank for as long as needed. If you can’t float the bag itself, a floating plastic container also works just fine.

Drip Acclimating

Once the temperatures are equal you can move on to the process of drip acclimating, which is the easiest and most stress-free way to acclimate new stock. All you need are a container, such as a bucket, and some airline tubing. A control nozzle for the tubing comes in handy but if you don’t have one there’s another way to control the flow.

How to acclimate your fish to a new aquariumGently place the fish and their water in the container. Start the water flow through the airline tubing from your aquarium to the container. The key is to regulate the flow so it’s just a gentle drip, which is either done by using the nozzle or by folding a piece of the tubing and fastening this with a rubber band to block part of the water. If you’re using the latter method you might have a little more trouble getting the flow as you want it (around three drops per second), but with a little fiddling it usually works out.

Tip: Your fish will appreciate a little cover in the form of a plant or even just some floating mesh. You’ll also want to put some kind of lid on the container: this prevents any jumpers from ending up on the floor and provides soothing darkness.

And now… you wait. Fishkeeping is a hobby for the patient, and acclimating is no exception. You’ll want to roughly quadruple the amount of water in the container, which obviously takes quite a while with such a slow water flow. Check back regularly to see if all is well, but leave the fish alone as much as possible otherwise.

After Acclimating

After around two hours the acclimation process is finished. Hopefully (and likely!) all of your fish will still be alive at this point, though despite your best efforts they are likely still quite stressed and not very happy. Time to move them to their new home and leave them alone so they can settle.

Grab a net and gently move your new additions to the aquarium (with as little air time as possible). Make sure the tank lights are off and keep them this way for at least 24 hours. Ignore the urge to feed the fish in an attempt to make them comfortable: they’ll be fine and it’s more important for them to get some peace and quiet. Once you turn the tank lights on the next day, keep a close eye on new fish for a while in case of disease or other issues.

Skip the Stress

Feeling intimidated by all the steps that are necessary to get new fish from A to B without any casualties? We can imagine. Luckily FantaSEA aquariums is here to take care of all aspects of setting up and maintaining an aquarium for you. All fish are quarantined to prevent disease and carefully acclimated to your aquarium by our knowledgeable staff. Sound good?

One of the most important aspects that fish keepers overlook is how to properly acclimate their new fish into an existing established tank. There’s a lot of fish that have met an untimely end due to improper tank acclimation.

What is Acclimation?

Have you ever traveled from the cold north of winter to a higher climate of the Caribbean or Florida? Or from sea level up to a higher altitude? You’ll find that it would have taken you a while to get used to the sudden change of climate. The same is true with your fish, and when you move a fish from one tank to another, they always need to be gradually acclimated to the new water conditions. This is true regardless of how far the fish have traveled, whether the fish have been shipped from a long distance, or simply moving them into another tank in your home. The most important water parameters that fish need to be acclimated to are pH and nitrates level, along with the water temperature.

How to acclimate new fish

There are a few ways of acclimating fish to a new aquarium, so let’s go through some methods.

  1. The first thing you should do is float the bag that the new fish came in for around 10 minutes.
  2. Next, get a container that holds around four times the amount of water that is in with the bag of fish. Only use a container that is used for aquarium use only, and make sure that the container has never been used for uses that have involved soap.
  3. Put your new fish into the container. Every few minutes, over the period of 30 minutes, take some water from the tank the fish will be going into, gradually putting the water in the container. The water you’re adding from the tank to the container (each time) should be around 20 percent of the amount of water in the container from the fish bags.
  4. After 30 minutes, use a net to fish when putting them in the aquarium. Get rid of the leftover water that’s in the container. It’s important to observe your new fish for as long as possible after introducing them into their new aquarium, as you want to make sure that they’re not getting picked on by the existing fish in the aquarium.

Use a quarantine tank

If you have a sophisticated aquarium setup, then all the new fish should spend 2 to 3 weeks in a quarantine tank before being introduced into the main fish tank. Quarantine tanks are used to make sure that the new fish aren’t carrying parasites or diseases that could have been in their previous tank. A quarantine tank can be as small as a 5 gallon tank, and all you need is a sponge filter that has been in the tank that they’ll be going into. Other things that you will need include a heater, light, and cover. You should monitor the fish every day during the quarantine period. Only once you are confident that they’re not carrying any parasites or diseases, can you put them into the main tank, using the method described above. Use the same acclimation process when introducing the new fish to the quarantine tank, and from the quarantine tine to the main tank.

Water changes

Before introducing new fish to the tank, you should do a 25 to 30 percent water change. The reason for doing this is if you don’t do regular water changes, then the nitrates in your tank have probably built up to high levels. Fish can deal with high nitrates, but only if they’ve been accustomed to the high levels over a long period of time. Nitrates can become problematic if you take fish from low nitrates, which is the case for the majority of tanks, putting them straight into an aquarium with high nitrate conditions. If your main tank nitrate levels are too high, then this could result in the new fish becoming stressed, even killing them.

There are a lot of fish stores that usually ask for a sample of your water if you’ve recently bought a fish that’s died soon after being purchased, as the store wants to check to make sure that they’re not going to be sending replacement fish into a high nitrates tank just for them to perish shortly again.

How to acclimate your fish to a new aquarium

Acclimate Fish – All aquarium fish are sensitive to rapid changes in their environment. A sudden change can send them into shock and lead to death. We care about them so let’s do things the right way.

Floating bags from the store in your tank is not enough. Many people use this method, but this is wrong! It does nothing to acclimate your fish! All it does is adjust the water temperature of the bag to that of your tank. It does nothing for other water parameters.

Whatever how long you float the bag, if the water in it has a pH of 7.6, that will be a big shock for your new friend if you pour it into a tank with a pH of 8.3. Lights can overheat the water in the bag.

How to Acclimate Fish to a New Tank?

The following procedures help to acclimate new fish to adapt nice and slowly to new water conditions. :


  1. As soon as you get home with new fish, pour the bags into a water bucket. To acclimate fish, the bucket should be big enough, so the new fish is reasonably covered with the water. Don’t use new water or water from your tank! Just use the water that came with the fish. You may acclimate more than one fishes in the same bucket. Any poisonous, toxic, or aggressive animals should be acclimated individually.
  2. Now set the bucket on the floor next to the aquarium or quarantine tank.
  3. Using a plastic airline tubing, set up and run a siphon drip line from the aquarium to the bucket.
  4. This procedure must be really slow, so we now need to adjust the flow. This is where the air valve comes into play. Using the air pump or air valve, adjust the water flow coming from the tank to the bucket (A loose “knot” tied in the airline would do). Water should go through the airline one drop at the time (one drip per second is good). This way, the water that came with your new friend will slowly adjust to the tank condition.
  5. From here, things goes pretty much by them self. Let it drip for a good 30 min to 1 1/2 hours. Hardy fish should do well with shorter dip time while sensitive species might need more. Once this is done, test water in the bucket to see if water parameters match that of your tank water. If the answer is yes, the acclimation is complete.
  6. It’s now time to introduce your new friend to your tank or in a quarantine tank. Use the container that will submerge in the bucket and place the animal it. Then, remove the bowl with just a little water and your animal. Gently submerge the container into your tank or quarantine tank (do not throw or drop the fish from above the surface of the water).

When you acclimate fish, try to avoid adding water from the shipping bag to your tank. You don’t know what’s in it. It may introduce diseases or other undesirable things in your tank. The best is to throw out the water in the bucket. You may also turn off the lights and leave them off for 2-3 hours after the fish are introduced. This will help reduce stress.

When introducing new angelfish into an existing tank, you don’t want any more conflicts than necessary. We’ve seen a lot of people suggest moving ornaments and decorations around to confuse the existing fish and prevent fighting. In our experience that seldom works with angelfish. Even so, lots of hiding places are a good idea, so the abused fish is more difficult to chase.

It is best to quarantine the new fish and start the introduction after it has recovered from its trip and change in water. The first thing to do is to put a divider in the tank you’re moving it to. The existing inhabitants are likely to be very territorial, regardless of their age or sex. Territorial aggression is the biggest threat to new fish. This is a situation where newly introduced fish are in danger of being seriously injured or killed. The divider will allow the new fish to get used to the tank and establish their own territories. You can buy a divider or make one from “egg crate” or other non-toxic materials like a good fish-safe reticulated foam. After a couple of weeks, it is generally safe to slightly move the divider to allow fish to swim to the other side. After a few days of this, it is probably okay to remove it completely. Just be prepared to put it back if there is any serious fighting.

Another technique is to introduce all the fish to a tank at once. If you are getting fish from different sources, it’s best to quarantine each source separately and then after the quarantine period, put them all into the community tank at the same time. This way, there will be no territorial aggression at the beginning.

There is a common misconception that it’s best to introduce fish of the same size. The thought is that they can defend themselves easier. We’ve found that this doesn’t work very well. It’s best to introduce new fish that are much larger or much smaller. Much larger fish can usually fend for themselves. Much smaller fish are often chased for a few minutes and then ignored after the large fish realize they can’t catch them and that they’re no threat. We’ve often times use small angelfish as dither fish for pairs. The pairs seldom are able to harm them and we find ourselves quickly looking for more tank-space as these “dither” fish do so well and grow so fast in those situations. In many instances the dither fish grew into the dominant fish in the tank over time.

Aggression is a tricky thing with angelfish. Tanks with the most aggression tend to the ones with the fewest angelfish. Those that are crowded seem to end up the most peaceful. If there are many fish in the tank, no one individual thinks it can defend a territory or safely breed, so they don’t even try. If you try this, remember that crowded tanks need far more maintenance and are prone to other problems because of the high density.

We hope some of these hints aid in your successful introduction of newly acquired angelfish.

Everyone needs time to get accustomed to a new environment, so does your newly purchased fish. Imagine you take a long trip to a foreign country, you will get a little bit of sickness after all. Same as your fish with the journey from a pet store aquarium to a temporary plastic bag and finally your tank. However, they may suffer more than sickness. Fish are very sensitive to even minor changes. Sudden changes in continuity, like the transport we described, may get them shocked and even perished.

In order to prevent it happening, we introduce you to the acclimation process below. By conducting it, your fish will have enough time to slowly and properly adapt to the new environment, your aquarium.

** IMPORTANT: Before you carry out the acclimation process, please ensure there are no lights on or around the tank where the fish will live (we want to emulate the shipping environment which the fish just survived by not exposing them to any bright lights to reduce the appearance of stress or trauma to the fish). Light shock can (whether it is from natural or artificial light) be unfavorable. Please note: Our fish coming out of the box will look very sluggish. Sometimes the fish even appear not to breathe. This is due to the tranquilizer and lower temperatures slowing the fish’s metabolism. Please make sure to acclimate the fish with our guide and your splashy pet will be splashy in a very short time.

Recommended equipment:

  • Airline tube; and
  • A 16oz cup or a bucket of up to 5 gallons.

A step-to-step acclimation process:

  1. Turn off aquarium lights (or place your aquarium lights to the moonlight setting). Also, make sure the room light where you unbox your fish is also dimmed.
  2. Float the sealed bag in the aquarium for at least fifteen (15) minutes – keep the bag sealed and do not open it yet. This step allows the water from the shipping bag to gradually match the temperature in the aquarium, while maintaining a high level of dissolved oxygen.
  3. Carefully empty the contents of the sealed bag(s) [including the water] into the bucket(s). Depending on the amount of water in each bag, this may require tilting the bucket at a 45-degree angle to ensure the fish are fully submerged. You may need a prop or wedge to help hold the bucket in this position until there is enough liquid in the bucket to put it back to a level position.
  4. Use airline tubing, set up and run a siphon drip line from the main aquarium to the bucket (you will need separate airline tubing if you are using more than one bucket in this process). Tie several loose knots in the airline tubing, or use a plastic or other non-metal airline control valve (using a valve is the preferred suggestion in this process; however, the tied knots will work well in lieu of using a valve), to regulate the flow from the aquarium. Additionally, we recommend securing the airline tubing in place with an airline holder (we suggest an algae magnet).
  5. Begin a siphon by sucking on the end of the airline tubing you will be placing into the bucket. When water begins flowing through the tubing, adjust the drip (by tightening one of the knots or adjusting the control valve) to a rate of about 2-4 drips per second.

When the water volume in the bucket doubles, discard half of the water and begin the drip process again until the volume doubles once more (which should take about one hour).

It is not a complicated process at all. However, it requires your patience and meticulousness. Just put a little bit more effort and you will find hard work pays off. Your splashy fish will happily splash around inside your aquarium upon the successful acclimation.

Demmer states that the plastic bags, though waterproof, allow gases to permeate. He experimented with identical bags of feeder guppies, one was floated in a tank, the other he put in a dry place with otherwise similar conditions. The fish in the floated bag showed signs of stress at one hour and death at four hours. The fish in the other bag were still lively when he released them back into an aquarium after six days. He offers no chemical theory of what’s going on, just the empirical evidence.

Demmer reports improved survival rates with new shipments to his store and with his retail customers’ fish when this method is no longer used. 2. Floating the bag, but opened (Enright). I have seen this method in at least one Aquarium book. The bag is “floated”, but tank water is added gradually to the bag. A clip (lettuce clip, clothespin, etc.) to hold the open bag against the side of the tank might be needed to keep it all from sinking. 3. Float the bag, but put a hole or holes in it to let tank water seep in. This can be a big hole (Demmer) or small toothpick size holes (Enright). The big hole method is really to let the fish swim out at their own volition. Note that this method allows the mixing of pet shop water with your tank’s water. . 4. Just dump the fish in, no real acclimation. Not really recommended by anyone but Fenner, but he does this to shipments of hardier fish, and they are put into a medicated tub, and then into a holding tank. He dislikes retaining any of the shipping water (this is long distance shipping) since it contains a host of bad things (pathogens, pollutants, metabolites).

  • Just open the bag (I assume you need to support the bag by putting it in a container and using clothespins to hold the bag to the container) and put in small amounts of tank water slowly. Alternatively, just pour the fish and water out into a holding (acclimating) container, and then add tank water. The addtion of water can be done by a dripline.
  • Dripline. Demmer, Coletti, and I like this approach. Even Fenner will use it for “touchy” fishes. See “Dripline Construction”, below for a summary of how to make one.

You can use a length of standard airline tubing. The trick is how to deal with both ends of it.

The end that goes into the tank needs to be secured. Colleti suggests using an airline gang valve with bracket. I suggest making an upside down “U” shaped device that hooks onto the edge of the tank. In my FAMA item, I suggested making one out of 3/16" rigid tubing and Whisper Swivels.

How to acclimate your fish to a new aquarium
Above: 3/16" rigid tubing bent so that it will hook over the edge of the aquarium.

Whisper Swivels are devices for making a 90 degree joint in an airline or airline/rigid tubing system. (And I don’t think they are made anymore.)

Since that time, I have found a better way: you can easily bend 3/16 inch rigid tubing by first soaking it in hot water and then bending it to form a “U” shape. A short piece of airline tubing on the end that goes into the tank insures that it will still work if the tank water level goes down.

  • A drip. You can put a knot in it. Colleti uses an airline tubing connecter, i.e., the piece that is sold to splice two pieces of airline tubing together. This is not adjustable. I prefer an inexpensive airline flow control valve (these often come in airline control kits). This is adjustable.
  • Someway to secure it to the acclimation container. (Or you could just let it dangle). My suggestion: get a lettuce clip, the type that has two solid flanges (the parts you squeeze to open the clip) one of the flanges has a hole in it to accommodate a suction cup. Remove the suction cup. Drill a 3/16" hole in the other flange. Insert the tubing through the hole vacated by the suction cup. Force the end of the tubing through the drilled hole. This may take some force (try pushing with a ball point pen). You want this fit to be tight so that the tubing does not move around. Insert valve.
    How to acclimate your fish to a new aquarium
    Above: a lettuce clip, suction cup removed, 3/16" hole drilled to allow standard airline tubing to pass through to hold an airline valve.

You can extend the tip of the valve by putting on a short piece of airline tubing. If you use a pliable type (Python brand is good or a silicone type), then you can start the siphon action with a turkey baster. The end of the baster goes not fit very well on tubing, but you can press it into pliable tubing and provide enough of a seal with pressure from your fingers.

The lettuce clip works on most thin rimmed containers, but will not work on really thick rimmed ones.

The final question is, how long of an acclimation period do we provide? Most authors prefer at least 30 minutes, but the longer the better. If the acclimation vessel becomes too full from the drip, excess water needs to be removed to allow for accomodate more tank water.

Freshwater fish montage
from Cardinal Tetra from
the Uraru Home Page Page Created by:
James S. Koga
[email protected]
last updated:
February 20, 2015


I find the process of acclimation to be stressful for myself, as well as the fish. I get home with those fish and I’m aware that the clock is ticking and I need to get them out of those bags and start the acclimation process – drat, where did I put that dripline, and did I really think that they should go into this tank or was it that tank? Fumble, stumble, and now there’s water on the carpet. You get the picture.

I hope that the information presented here will help you to make an informed choice of an acclimation method, and will be of some benefit to your fishkeeping.


Coletti, Ted. Acclimation: A Better System. Tropical Fish Hobbyist , XLIII, No. 12 (#474) (August 1995): 146-151.

Demmer, George. To Float or Not to Float? Freshwater and Marine Aquarium , 18, no. 7 (July 1995): 35-38.

Enright, Michael P. How to Bring ‘Em Home Alive and Keep ‘EM Alive. Freshwater and Marine Aquarium , 17, no. 12 (December 1994):210-215.

Fenner, Bob. Guerilla Acclimation Methods, or Acclimating: My Way. [Aquatic Environments Column]. Freshwater and Marine Aquarium , 17, no. 10 (October 1994): 99-104.

Koga, James S. Improved Dripline for Acclimation. [For What It’s Worth feature] Freshwater and Marine Aquarium , 19, no. 4 (April 1996): 222.

Once your package arrives, it’s important to start the acclimation process right away. When you properly acclimate your coral, you ensure their health and survival as you introduce them to their aquarium home. Make sure you fully examine the shipping box and your coral for any damages or leakage. If you find any signs of damages, dead on arrivals (DOA), or have questions, don’t hesitate to contact us via email or phone.

Temperature Acclimation

To start, you will need to acclimate your coral to the temperature inside their new aquarium home. Float the bag with your corals inside the tank for about 15 minutes. This ensures that the temperature inside the bag matches with that of your aquarium.


Another important habit to maintain your tank is dipping. Dipping can be a stressful process but it’s worth doing to avoid problems with your frags. Use your preferred dip. Be sure to follow the manufacturer’s instructions carefully so you avoid stressing your new arrivals. You should also use a pipette to stir the water inside the dipping container.


Inspecting your new corals is very important. Take a good look at your new frag and make sure it looks good. If you have any questions, please be sure to give us a call. Any of our experienced reef keepers are ready to help you with anything you need!

Placement tips

Choosing the best placement for your coral depends on a few factors. Make sure to refer back to the preferred flow and lighting on its label. We recommend adhering the corals to a rock by using coral glue gel. Also, give your corals at least 24 hours to get used to your new tank so that they can fully open.

3 Day Arrive Alive and Thrive Guarantee

We are committed to your customer satisfaction. If your frags die within 3 days of delivery, we’ve got you covered. Send us a picture of your deceased coral within 3 days after arrival and we will replace it or provide you store credit for the amount that the coral was worth.

The acclimation process is such an important part of keeping your corals healthy. Be sure to send any questions or concerns to our reef consultants. We at REEFTIDE would like to thank you for your continued support. Happy reefing!

1 comment

Just wanted to say how well my first order of corals are doing.
For my first corals I ordered 4 frags a hammer and Cody anemone and they are all doing amazing.
Y’all have incredible quality and I’ll be ordering more.
But dang some of these corals are crazy expensive had no idea there were 900 dollar corals. 😂