Acclimating salt-water fish to brackish or fresh water

459b

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Not sure if this is the right place for this info.
Thought this patent is worth a read.
I know that alot of fish can survive both fresh and salt water (like fingerfish and mullet), and have even seen trout thriving in salt water. Never thought anyone had ever tried it on chromis, damsel, clown, tang, surgeon and grouper.

Acclimating salt-water fish to brackish or fresh water - Patent 6016770
 
I'm talking under correction now - it should be possible with something like sugar. Yes, you read correct. Sugar. It all goes about the SG of the water, not so much the salinity. Correct me if I'm wrong.
 
Hi 459b - I am not too sure about the acclimation method - but I KNOW that saltwater fish can survive in fresh water. In January 2007, I had a huge tank crash, where all the inverts in my tank died. I had 9 fish at the time, and 6 survived, and seemed QUITE happy to live in FRESH RO water (no salinity left in my tank at the time/no salt)....
The fish that survived, was:
- 2 damsels
- 2 occelaris clownfish
- 1 fire goby
- 1 manderin
Unfortunately, due to the lack of pods in the tank at the time, my manderin too died about 1 week later....
 
i just found it funny that someone actually applied for a patent. And he went throught all that just to kee psalt water fish with freshwater fish. I wish it said how many fish he killed.
 
Hi Guys to me it is just not fair to the poor creatures that must tolerate this on a permanent basis. Imagine a beautifull Flame Angel or Emperor tang swimming around with a few guppies- it is a disgrace to the hobby, both Freshwater & Marine!! Also imagine what this would do to the lifespan of the fish or the exclusivity of marine tanks?
 
Yip Jacques, a emergency is understandable but doing this for your own pleasure...
 
dont think its cruel, in all case that is. Some fish ca nsurvive both conditions quit comfortably.
it would be funny to see a flame angel swimming in a tank with neons.
i wonder if the saltwater fish would be more/less susceptible to freshwater pathogens?
 
dont think its cruel, in all case that is. Some fish ca nsurvive both conditions quit comfortably.
it would be funny to see a flame angel swimming in a tank with neons.
i wonder if the saltwater fish would be more/less susceptible to freshwater pathogens?

It's is just not natural, I know some Brackish species like Archers, monos, mollies and puffers do this quite comfortably, but to do this to a angel, tang or butterfly is just not right! If nature intended it to be this way it would've been!
 
Maybe not cruel, but certainly unnecessary in my opinion, brackish fish can survive in both, through natural selection over millions of years, so to expect a fish to convert over even weeks is, at best, misguided.
 
so i take it noone is going to try this?

Not unless i get into a situation like Jacques did and have no choice, but it would only ever be temporary, i don't see a need for it, we are perfectly capable of creating sea water for them to live in, so whay would you want to put them in fresh?
 
to clarify things, im not trying to put any in freshwater. I was just doing some reading about puting freshwater fish into saltwater. Just found it interesting because of how many people say that even a slight drop in salinity will cause your fish to die.
 
to clarify things, im not trying to put any in freshwater. I was just doing some reading about puting freshwater fish into saltwater. Just found it interesting because of how many people say that even a slight drop in salinity will cause your fish to die.

No harm in raising awareness, but generally fish will survive in all sorts of salinity, it tends to be inverts and corals that are less hardy. Fish only tank owners tend to run lower salinity, as do many lfs, but i think there is a difference between "survival" and "acceptible living standards"
 
most definitely. When you say, run at lower salinity, how much lower is that?

Many lfs run at around 1.020, fish only tanks are reccommended to do the same, this is supposed to suppress/remove parasites such as white spot, it has never shown to have negative affects on the fish.
 
that doesnt sound that low. do you know of any cases where people run really high SG?


As far as i know if your SG is too high it can burn the fish (bit more to it than that - but not so great on chemistry):(
 
I have seen fish only tanks run at 1.010SG to get rid of white spot, the white spot goes but the fish are perfectly happy. No pods or SW bactria can live at this SG but fish can do fine. As well as making it easier for the fish to get FW into there system, i heard that higher SG is not good bnecause of that(but not bad at all)
So dont put your fish in 1.000SG but to lower it is actualy very good for the fish
ONLY IN FISH ONLY TANKS IS IT GOOD
 
As far as i know if your SG is too high it can burn the fish (bit more to it than that - but not so great on chemistry):(

What happens with fish at too high SG, is that they have to work TOO hard at getting fresh-water from the external water supply.

This is how it works:
- Fresh water fish, generally have to excrete a LOT of water, because the SG of their body fluids are much higher than that of the surrounding water - this means that their bodies take up MUCH more fresh water by way of osmosis than what is necessary/good for them - therefor "weeing" a LOT
- Salt water fish have the opposite effect - salt water fish have to keep as much fresh water in their bodies as possible. S/water fish have a method of "extracting" the fresh-water from the external salt water that they live, and keep as much fresh water in their bodies. Because the SG of the bodily fluids of fish are much lower (generically) than that of the surrounding water, they only excrete fresh water (wee) when they have accumulated enough fresh water in their bodies... This process places quite some strain on the fish's "kidneys"...

SO - the higher the SG - the more strain on the fish. The lower the SG - the less strain on the fish!
:thumbup:
:peroni:
 
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