Acclimating Salt-water Fish To Brackish Or Fresh Water

[seffieuk]

Spending a few hours surfing - Bank Holidays, I love em Anyway, came across this:


http/www.freepatentsonline.com/6016770.html

Has anyone else tried to take marine fish down to this low an SG?

DETAILED DESCRIPTION OF THE INVENTION

The natural habitat for salt-water fish generally has a salt content of about 1.022. The process for acclimating a salt-water fish to water that contains substantially less salt than its natural habitat, requires placing the salt-water fish in water having about one half the salt content of its natural habitat. The salt content is then slowly reduced to the desired concentration.

In a preferred embodiment, fish is initially placed in water having a salt content of about 1.012 to about 1.01. The salt content is reduced by increments of about 0.0005 to about 0.003 specific gravity while the fish is allowed to acclimate to each new environment for at least about one week per 0.0005 specific gravity increment.

In a more preferred embodiment, the fish is initially placed in water having a salt content about 1.011. Then, the salt content is reduced by about 0.001 approximately every two weeks.

One can stop the acclimation process at any desired intervening salt concentration. For example, one can acclimate the salt-water fish to fresh water or to water having a salt content of about 1.001 to about 1.003.

It is expected that this acclimation process is applicable to most salt-water fish. Exception may include the more primitive fish such as sharks, rays, coral or anemone. Preferred fish for the process include chromis, damsel, clown, tang, surgeon and grouper. Particularly preferred fish for this acclimation include Chromis viridis, Chrysiptera starcki, Chrysiptera cyanea, Paraglyphidodon oxyodon, Pomacentrus coelestis, Premnas biaculeatus, Amphiprion leucokranos, Amphiprion percula, Amphiprion clarkii, Amphiprion ephippium, Amphiprion sebae, Dascyllus aruanus, Dascyllus trimaculatus, Dascyllus melanurus, Zebrasoma veliferum, Zebrasoma flavescens and Cromileptes altivelis.

The pH of salt water is about 8.0 to about 8.4 while that of pure water is 7.0. The pH of natural fresh water is often less than 7.0 because of dissolved acidic solutes in the water. As one lowers the salt content, especially from about 1.003 down, the pH also drops. In order to keep the salt-water fish in good vigor, the pH of the water should be maintained at about 7.4 to about 7.5. This is accomplished by methods well-known in the art, such as by placing a dead coral in the aquarium to act as a natural buffer, or by adding small amount of sodium bicarbonate to the tank.

In all other respects, care of the salt-water fish is the same as if they were in salt water. A varied diet, maintaining the temperature at about 78.degree. F., use of vitamins are examples of normal salt-water fish care.

In addition, when salt-water fish is introduced to an aquarium, one must equilibrate the temperature of the initial water holding the salt-water fish with the temperature of the aquarium water by methods known in the art. For the purposes of the invention, every time one introduces the salt-water fish to water having a different salt content, the temperature of the old water and the new water should be in equilibrium. As an example, when the salt-water fish is carried in a plastic bag to an aquarium, the bag is placed in the aquarium water for about 20 minutes before the contents of the bag is released into the aquarium.

The invention also provides a salt-water fish that can live in water that contains substantially less salt than its natural habitat. Preferably, the salt-water fish can live in fresh water or water having a salt content of about 1.001 to about 1.003.

Further, the invention provides the ability to keep both salt-water fish and fresh-water fish within the same aquarium.

Can you believe that someone actually has a patent on this!

Looking forward to hearing your views

 

[nmonks]

Has anyone else tried to take marine fish down to this low an SG?

Only possible with euryhaline fishes. This is science. Freshwater fishes cannot adapt to salt water, nor salt water fishes to freshwater, unless they are euryhaline fishes that possess the physiological systems to live in both types of environment. Most do not.

In a preferred embodiment, fish is initially placed in water having a salt content of about 1.012 to about 1.01. The salt content is reduced by increments of about 0.0005 to about 0.003 specific gravity while the fish is allowed to acclimate to each new environment for at least about one week per 0.0005 specific gravity increment.

Don't know what the "preferred embodiment" is, but if you bought a marine fish from the store, dumped it into a bucket with SG 1.012, and then waited for it to adapt, you'd get a dead fish. Euryhaline fishes can adapt within an hour, even instantly, so faffing about 0.0005 changes every week is stupid.

One can stop the acclimation process at any desired intervening salt concentration. For example, one can acclimate the salt-water fish to fresh water or to water having a salt content of about 1.001 to about 1.003.

Insane. Dead fish.

It is expected that this acclimation process is applicable to most salt-water fish. Exception may include the more primitive fish such as sharks, rays, coral or anemone.

Corals and anemones aren't fish.

The pH of salt water is about 8.0 to about 8.4 while that of pure water is 7.0. The pH of natural fresh water is often less than 7.0 because of dissolved acidic solutes in the water. As one lowers the salt content, especially from about 1.003 down, the pH also drops. In order to keep the salt-water fish in good vigor, the pH of the water should be maintained at about 7.4 to about 7.5. This is accomplished by methods well-known in the art, such as by placing a dead coral in the aquarium to act as a natural buffer, or by adding small amount of sodium bicarbonate to the tank.

Wrong in so many ways. If this worked, everyone would be keeping clownfish in goldfish bowls. But it doesn't work this way.
The invention also provides a salt-water fish that can live in water that contains substantially less salt than its natural habitat. Preferably, the salt-water fish can live in fresh water or water having a salt content of about 1.001 to about 1.003.

Further, the invention provides the ability to keep both salt-water fish and fresh-water fish within the same aquarium.

If they're euryhaline fishes, then certainly this is possible. You could create an aquarium that had both goldfish and Emperor snappers in it, maintained at around 25% normal seawater salinity. But most marine fishes aren't euryhaline, so this doesn't work.

The whole thing has to be a joke. There's no way it could work.

Cheers, Neale

 

[andywg]

I agree with neale here.

While I prefer to quote to scientific literature, I shall quote from Scott Michael's "Reef Fishes Volume 1" where he talks about the salinity of water and its effects on keeping marine fish. He does cite his references, but only at the end of the chapter and not after each relevant point. The below is from page 228 of the above book:

At a lower salinity, fish have to expend less metabolic energy to conserve the water in their body tissues. In fact, many coral fishes can be withstand salinity levels approaching that of freshwater for short periods of time (e.g., 1 week). Emperor Angelfish (Pomacanthus imperator) have been kept at a salinity of 7ppt with no apparent ill effects. These fish were not "stressed" as indicated by the lack of change in their serum cortisol and glucose levels. The angelfish also continued to feed and did not behave abnormally. The lethal limit for the Emperor Angelfish was found to be a salinity of 5ppt; at this salinity all individuals died within 3 days. Therefore while fishes from coral environments have long been thought of as being stenohaline (only tolerating a narrow salinity range),most species studied to date are actually physiolgically euryhaline (tolerating a wide range of salinities).

There are some important things to remember about the above. First off, sea water is around 35 ppt, so while many of the reef fishes can tolerate lower levels of salinity than originally expected, once it is below 5ppt (about 14% saltwater) then the fish will die very quickly, so you cannot acclimatise most marine fish to freshwater, or anything very close to it.

There are some brackish species that can tolerate long periods of any salinity, though even these do best when given the chance to vary the salinity between fresh and marine. I am not aware of any fish (though no doubt neale is) that is just as happy in freshwater for all its adult life as marine.

Going the other way is just as difficult. Some fish can handle some quite high levels of salt in their water, but many (such as the softwater amazon fish like the Pimelodids, or neon tetras and such) wil not tolerate levels of salt that would even be described as brackish, let alone marine, for any period of time.

The bottom line is, there are a few hardy fish that can tolerate being moved from one water type to the other, but this is becauyse they can do it in the wild. You are not "aclimating" the fish to different water conditions, you are just placing it in less than ideal conditions, but some which the fish is able to survive in.

Edit

I have looked at the page, the fact this patent has been filed by someone who can't seem to tell the difference between salinity and SG makes me feel there is no science behind their patent claim.

 

[nmonks]

AndyWG,

I'd perhaps take issue with Scott Michael's use of the word "euryhaline" -- for me, that implies a fish (or invert) that is able to live more or less permanently at a range of salinities. So a scat is euryhaline fish, insofar as it can be kept for months, even years, in freshwater, brackish water, or marine water. Maintaining marine fish in brackish water has been quite widely studied because doing so can be useful (e.g., for aquaculture). There's an excellent paper here doing this with pufferfish, and it describes things like changes in blood composition and mortality rates. Nice pictures, too!

My understanding is that virtually all marine fish will thrive at SG 1.018, which is about 80% seawater salinity.

Cheers, Neale

 

[mlawson]

You must remember that Marine fish are very different to freshwater fish. In freshwater, osmosis is different. The water freshwater fish live in is weaker than the fish, so to avoid pressure building up in the fish they must drink as little as possible and excrete as much as they can. On the other hand, marine fishes live in very salty environments where the water is stronger than the fish, therefore they must constantly drink as much water as possible and excrete little. This is why most fish except for euryhaline fish simply wont tolerate going into different types of water.

Mike

 

[andywg]

AndyWG,

I'd perhaps take issue with Scott Michael's use of the word "euryhaline" -- for me, that implies a fish (or invert) that is able to live more or less permanently at a range of salinities. So a scat is euryhaline fish, insofar as it can be kept for months, even years, in freshwater, brackish water, or marine water. Maintaining marine fish in brackish water has been quite widely studied because doing so can be useful (e.g., for aquaculture). There's an excellent paper here doing this with pufferfish, and it describes things like changes in blood composition and mortality rates. Nice pictures, too!

My understanding is that virtually all marine fish will thrive at SG 1.018, which is about 80% seawater salinity.

Cheers, Neale

I must admit, I would tend to agree with you. Michael seems to be inferring that most coral fishes are short term euryhaline to a degree, though very few (if any) can be classed as able to survive at freshwater or very light brackish.

He does lead into the benefits of being able to reduce salinity in fighting parasites and such.

That link looks very good, when I have a little more time, I fear I shall read and digest. Cheers.

Andy

 

[pica_nuttalli]

thank goodness he has a patent on that so no-one else can steal his stupidity

 

[Tolak]

thank goodness he has a patent on that so no-one else can steal his stupidity

I almost choked on some leftover lasagna!

 

[jtipton]

I stumbled upon this old post and wanted to follow up. Keeping fresh and SW fish together is possible. Most of the approaches involve replacing the salt compounds with sugar compounds (monosaccharides and polysaccharides). Here is a link to a related article:

Wonder Water

 

[seffieuk]

Oh I can't wait to see how our brackish experts respond...................... It is fasinating

 

[andywg]

Sounds like rubbish to me, and they took some BW tolerant FW fish and they survived for some short period (no stories of how long any of this lasted for). I will be interested to hear nmonks' view on this, however.

 

[jtipton]

Don't get me wrong. There is a big difference between possible, and a good idea. The BW fish were used because of their better temperment with SW fish, but the solution works with other FW fish as well.

 

[andywg]

Care to provide some evidence of FW fish living for a good 3 years or so? If it works, why isn't it still on sale now?

And so, let us move more into the science side of it.

by putting certain types of "sugar" compounds of monosaccharides and polysaccharides together, fresh water could be modified to maintain successfully both fresh and saltwater fishes in the same water environment.

So they are dealing with freshwater it seems here, and rather than putting salt in it, they are putting sugar in it, yet then they go on to speak of primary and secondary freshwater fish. If they have indeed just put sugar in FW then it will not matter about the FW fish.

From the way they have described it I reckon they have basically got a tank to about 25% seawater (brackish, in other words) and acclimated some FW fish up to the brackish level, and some marine fish down (note the comments above about SW fish being able to survive in reduced salinities).

I simply do not see how having "sugars" (or carbohydrates) in the water will prevent the fact that either a FW fish will have the intake of sodium and chloride ions become passive at the same time as their body is set up for active transport (as in, it will start to become inundated with salt) or that a marine fish will start to have water come in via a passive transport when their body is set up to absorb large amounts of water (the body will have too much water in it).

The words "oil" and "snake" come to mind.

 

[Corleone]

I don't see any way you can replace a salt with a sugar. Salt is a dissolved ionic compound, sugar is a ring shaped carbon based organic molecule. Their chemical similarities are nil. Looking around Kordon's site, different pages give different reasons for the product being discontinued. I counted three different and contradictory reasons.

Considering this stuff originated in the 50's, the definition of "successful" fish keeping was probably quite a bit different. Searching google was pretty hard, because of the number of brands that combine the words water and wonder, but I did find a forum post by somebody who claims to have kept convicts and clowns together for a year using the stuff before it went off the market, but he can't remember any details and is a bit too cavalier about it for me to believe.

If the stuff still existed or could be replicated, it might be interesting (from a scientific standpoint) to try. It could revolutionize so many fields (not just fishkeeping) that if the science existed, somebody would be trying it. Food fish farming alone could be revolutionized by it.



Mostly unrelated, but I once saw a picture of the most stunning tank I've ever seen. It was divided into a front half and a back half, each one quite large. The front half was a large discus tank, and the back half had marine fish. Gave quite a good illusion that the fish were living together.

 

[el_vulture619]

I want some wonder water!! Then Ill put in some Kool-Aid!! Throw my percula clowns from my nano= Kool-Aid clowns!

I have a brass magnet for sale too!!