TwoTankAmin
Fish Connoisseur
A quick observation re most stores which sell fish. Their ideal holding period for most fish before they are sold would be a few minutes. But that is not how it works. But they do turn over fish in fairly short order. This means even if their water conditions are not ideal for the fishm those fish are in and out fairly fast.
Next, most of the people working in the fish depratments of pets stores and some of the flocal fsh stores are not all that well educated on the fish. Their job is to sell customers more, not less.
Finally,it is not possible to acclimate fish to clearly different condition in a matter of hours. There are internal biochemical processes which have to adapt (if possible) and this takes weeks not hours or even days. I have not acclimated new fish in at least 15 years and likely more like 18. I lop and drop. Fish out of the bag and into the home water ASAP with no bag water going into the tank. If I am getting enough to be going into multiple Q tanks, I may float the bags of fish goint into each tank to sort them, not to do anything about temperature.
Consider that in most lakes and rivers the deeper one goes, the colder the water gets. Do we think fish go up and down very gradually to acclimate to temperture changes? Or how about fish which live in water where there are seasonal changes. To induce some of my plecos to spawn I will raise the water temp from the mid 80sF to the low 90s and when it is time to simulate the seasonal changes I will drop the water temp into the high 70s in 24 to 36 hours. This doesn't harm them, it induces them to spawn, hopefully.
Yes there arecertain species which are much less able to live in a range of parameters. Consider the devils hole pupfish in Nevada, it is found in only one place in the world:
"Devils Hole Pupfish
Earlier pluvial (wet) periods allowed colonization of present sites; subsequent xeric (dry) conditions served to isolate the aquatic habitats, with the result that the inhabiting organisms have differentiated and evolved into the relict species found today. The Devils Hole pupfish have been isolated 10,000 to 20,000 years, longer than any other in the Death Valley system. Devils Hole itself is a water-filled cavern cut into the side of a hill. The cavern is over 500 feet (152 m) deep and the bottom has never been mapped. Devils Hole provides its resident pupfish with conditions of constant temperature (92°F, 33°C) and salinity, unlike the fluctuating environments of many other pupfish. Although pupfish have been found as deep as 66 feet (20 m), the fish forage and spawn exclusively on a shallow rock shelf near the surface, feeding on the algae and diatoms found there. The Devils Hole pupfish is considered an annual species, with the historic population fluctuating between 100 - 200 in winter and 300-500 in late summer. Research indicates that pupfish population numbers respond primarily to the amount of algae present on the shelf. The algal growth depends, in turn, on the amount of solar radiation the shelf receives and the concentration of nutrients in the water. Finally, recent evidence suggests that nutrient availability is highest when the cave is used by barn owls (Tyto alba) as a roosting/nesting site. The owls increase the pool nutrient levels by casting nutrient-rich pellets into the water."
https://www.nps.gov/deva/learn/nature/devils-hole.htm
Attempts to remove a few of the fish and to breed them in captivity have all failed miserably. So here is a perfect example of a fish that no amount of acclimation can make it possible to relocate them from the wild. But this is an exception not the rule. As long as there is a range of parameters specified for any species,and as long as it is within those parameters, it should be able to live a normal life. In fact, well cared for fish in aquariums can live longer than their normal life expectancy.
Next, most of the people working in the fish depratments of pets stores and some of the flocal fsh stores are not all that well educated on the fish. Their job is to sell customers more, not less.
Finally,it is not possible to acclimate fish to clearly different condition in a matter of hours. There are internal biochemical processes which have to adapt (if possible) and this takes weeks not hours or even days. I have not acclimated new fish in at least 15 years and likely more like 18. I lop and drop. Fish out of the bag and into the home water ASAP with no bag water going into the tank. If I am getting enough to be going into multiple Q tanks, I may float the bags of fish goint into each tank to sort them, not to do anything about temperature.
Consider that in most lakes and rivers the deeper one goes, the colder the water gets. Do we think fish go up and down very gradually to acclimate to temperture changes? Or how about fish which live in water where there are seasonal changes. To induce some of my plecos to spawn I will raise the water temp from the mid 80sF to the low 90s and when it is time to simulate the seasonal changes I will drop the water temp into the high 70s in 24 to 36 hours. This doesn't harm them, it induces them to spawn, hopefully.
Yes there arecertain species which are much less able to live in a range of parameters. Consider the devils hole pupfish in Nevada, it is found in only one place in the world:
"Devils Hole Pupfish
Earlier pluvial (wet) periods allowed colonization of present sites; subsequent xeric (dry) conditions served to isolate the aquatic habitats, with the result that the inhabiting organisms have differentiated and evolved into the relict species found today. The Devils Hole pupfish have been isolated 10,000 to 20,000 years, longer than any other in the Death Valley system. Devils Hole itself is a water-filled cavern cut into the side of a hill. The cavern is over 500 feet (152 m) deep and the bottom has never been mapped. Devils Hole provides its resident pupfish with conditions of constant temperature (92°F, 33°C) and salinity, unlike the fluctuating environments of many other pupfish. Although pupfish have been found as deep as 66 feet (20 m), the fish forage and spawn exclusively on a shallow rock shelf near the surface, feeding on the algae and diatoms found there. The Devils Hole pupfish is considered an annual species, with the historic population fluctuating between 100 - 200 in winter and 300-500 in late summer. Research indicates that pupfish population numbers respond primarily to the amount of algae present on the shelf. The algal growth depends, in turn, on the amount of solar radiation the shelf receives and the concentration of nutrients in the water. Finally, recent evidence suggests that nutrient availability is highest when the cave is used by barn owls (Tyto alba) as a roosting/nesting site. The owls increase the pool nutrient levels by casting nutrient-rich pellets into the water."
https://www.nps.gov/deva/learn/nature/devils-hole.htm
Attempts to remove a few of the fish and to breed them in captivity have all failed miserably. So here is a perfect example of a fish that no amount of acclimation can make it possible to relocate them from the wild. But this is an exception not the rule. As long as there is a range of parameters specified for any species,and as long as it is within those parameters, it should be able to live a normal life. In fact, well cared for fish in aquariums can live longer than their normal life expectancy.