I could not disagree more with the above for numerous reasons.
It is not possible to acclimate fish to anything in a matter of minutes or hours. As far as I am concerned attempting to do so does more harm than good. Any harm from potential ammonia is due to acclimating fish not shipping them. This is why people who understand this plop and drop and do not try to acclimate them.
I have watched how a major transshipper outside of the NYC airports handles the arrival of a ton of boxes arriving from all over the world. The incoming boxes contain a lot of fish, They are opened, the fish are dumped out and immediately sorted by numbers based on customer orders. They immediately go into new bags with new water and then they go into the boxes being prepared for picked-up by the buyers.
I have received some of those fish. But, because i was helping a friend here is how things went. I got severl boxes of fish and they went into my car. Most of the fish were not for me. I then drove a couple of hp=ours from NYC to N. Philly where I med the imported in the parking lot of a large mall. My fish often got rebagged as only part of the order was for me. This did not involve new water, we used he water in which I picked them up.
This transfer process and some conversation took about 40 minutes and we both head home. The drive we both had to make took anywhere from a 2 to 5 hours based on traffic. Both of us plopped and dropped out fish into tanks ASAP when we arrived home. Losses wire anywhere from 0 to a few fish.
I have my own system for what I do when new shipped in fish arrive at my home. I remove the outer bag and then based on how many species I have and how many different tansk they are about to be put in, I do one of two things.. When multiple bags goe into multiple tank I float the new bag in the assigned tank. I do not do this for acclimation reasons as I then go from tank to tank to opening the bag and pouring it through a net over a bucket and I then put the fish into the tank ASAP.
if I have a bag with 20 fish which will goe into two or more tanks I will empty the bag and its water into a bucket and net out tge fish and put them into their assigned tanks. All of this is done rapidly but not but carefully. The goal is to kept all of the fish out of their bags and into their tanks as fast as I can with no acclimation of any sort.
Sometimes, I may turn off the tank light for a bit after the fish are in their new home. I also will feed the fish not long after this.
So why do the new fish immediately bolt for cover and may behave a bit "confused?" There are several reasons. First, they have been in the dark from most of the trip from where the went onto the box and when they go into a tank. So they have gone from dark to light which can be unsettling. Next, the water along the way from where they originated, even with heat or cold packs as needed, still experience a temperature drop in transit.
So the fish are going from cooler water which has slowed their metabolism and they have been the dark and are likely sleeping most of the time as well. So, they are going from cooler and darker into light and into warmer water. But there is more, They are out into a totally new environment with which they are unfamiliar and which often has other fish maybe of different species which is also unsettling. But there is nothing harmful in this but it is also toally new. And then there is the fact that they have not eaten for some time, So they are also hungry.
All of this can make fish be unsettled. How long it takes for them to adjust and overcome the Newwnes of it all can take time for the fish to adjust. This does not mean acclimate it means ti become more at ease with where ythey were and where they now are.
Different species will take more or less time to adapt and to become at ease with their new environment. Some fish seem to accept it all and be at ease fairly fast while others may need a day tor two. They d not know there are no predators to avoid, they have not learned to navigate the new environment. They need to explore it amdbecome familiar with it.
And rhen their is the bio-chemistry of what happens in the bag water during the trip from where they started to when they arrive in their new home. Assuming they have been purged and properly packed things change. Properly means the water in the bag is clean, and the proper parameters. So it has no ammonia etc. in it But as the fish breathe, they are putting CO2 and ammonbia into the water. And this combination protects them from the ammonia. The CO2creates some acid in the water which drop the pH. This wirks to turn the NH3 they exhaled in the form of ammonium, NH4 which is way way less harmful.
The danger occurs when the bag is opened at their final destination. When the bag is opened there is a fairly immeduate gas exchange which lowers CO2 leverls which reverses the process of turning the NH3 into NH4. Plus tha bag water has degraded if the fish pee or poop along the way even when they have been purged before shipping. The bag water is the enemy here and the longer the fish are allwed to reamian in it after the bag is opened, the more harmful is become for the fish.
This is why we plop and drop. The longer the fish have been in the bag the more iportant this is to be doing. Here is what I do know havinf read a lot of research papers involving fish and a myriad of reserach questions looking for answers. the first step in the reserach is to acclimate th fish involved for anywhere froma week to a few weeks before the experiment begins. If acclimation were a few minute s or a few hours process, why do we thing the scientist take so much more time doing this?
Then the fish go through the experiment and the testing begins. often this requires killing some umber of fish to get to information on what changes they gave undertone. And what the researchers always find is that certian physiological adaptations take a week or two to menifest. These changes are what is required for fish to acclimate to clearly new parameters. However, when the parameters are so hreat or of such a naturte as the fish cannot adapt, they mat die. How and why is a part or the research.
So, now i have my bew fish in their tanks and I watch them over the next few days and ostly theeyadjust to their new environment, they do not hide, they interact well and the also eat well.
Nore often than not I am getting new fish after dark/I have pciked them up at the aiport late evening, or I have bought them at an acution and they do not arrive home until after lights out uin the tank where they go. So I do not see them untim the next day. Spmetime they are already comfortable and i can spot them but other times they may still be a bit intimidated and inclined to hide, But this does not last very long. They always are happy to get fed and that will usually bring them out of hiding.
Fish need time to adjust to their new home. they need to become familar with the latout si they learn where tey can hif if they feel the need to do so. For me a perfect example of this were discus. The first few water changes iw ould do after they arrived would cause them to hide. AAnd then suddently this stopped and I actually hade to nudge them out of my way so i could vacuum or more something around in the tank. They have gone froma state of fear and hiding to be getting in my way and my gavng to give thema small push to get them out of my waty
All of the nervousness and fear thay showed when they first arrived is gone. They have become comfortable with their new home. Of course a lot of this requires my help. The tank nust be aproper size, the parameters must be withing the range where thay wiil trhive and the food they are getting msut be both good quality and something they are happy to eat and porperly nutricious.
A lot of what may cause issues with new fish has more to do with us than anything else. Slow acclimation is often the cause as explained above. Bag water becomes more dangerous the longer the fish are in it.
While I am not a big fish busienss I have both received and shipped a fair number of fish over the past 2+ decades. I lose very few in either direction. I have worked with mostly very expensive fish when it came to what I had breeding. I have recived boxes with over $10,000 worth of fish. I have shipped out boxes with over $5,000 worth of fish in them. I guarantee live arrival. The incoming fish were not easy to find and I want no deaths or other issues when the fish are coming my way or I am sending them out.
Over the years my greatest losses in what I shipped out were from toxic shipping bags a problem which was rampant a couple of times over the years. I have also won a few fish on AqauBid which were either poorly prepped and bagged and which were wither DOA or which had issues soon after arriving.
But the majority of sellers want their fish to arrive alive and healthy. Folks whose fish do not usually do not last long as sellers. Word gets out. And never forget that old saying, "Fool me once, shame on you, Fool me twice and shame on me."
Most sellers who have been around for a long time and this is because they sell and ship healthy fish and they kow how to pack and ship them. The biggest problem tends to occur with the lower priced ship. Of one buys acouple of 100 tetras for 50 cents a fish that sell for $3 or $4, replacing DOAs is not costly. If one sends out fish that sell for $150 each and they are DOA, one is going to lose a lot of money, especially if they bought them rather than bred them.
A lot of the probleems with new fish being DOA or unhealthy and dying down the road are the result of people trying to save money and to pat less for the fish. What I know is that one live haelthy fish arriving has to be worht at least the cost of 3 DOAs. It is up to us to learn form what breeders or sellers we use and also to learn how to get them from the bags in which they arrive and itn their tanks without doing harm.
I polop and drop for a reason and I have paid as much as $1,000/fish for a box of 10 fish. I do not lsoe many fish coing in or going out. Mostly, it happens due to delays in transit time.
One last observation here. Going back in time before there was the internet and FexEx etc, it took a lot more time for fish to get from their natural wild environment to wherever they were going. The longer fish are in bags, the greater the potential there is for problems. That part of things has not changed even as the transit times have become shorter and how much more is known about this process and the potential causes of failure.
One example is how I learned to put a piece of Poly-Filter in the bags with fish or shrimp which helps absirb bith organics and ammonia. Thos allows me to reduce the amount of water needed to keep the fish safe and that means a lower cost for shipping.
