Keeping Salt in the freshwater Aquarium?

Hypatia

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May 1, 2006
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In a thread were I was asking about PH...
HappyChem, Roan, and I got into a discussion about salt added to the freshwater aquarium for guppies (and other livebearers). I wrote that I had been told that guppies like salt in their water, and Roan wrote about why that is not healthy for freshwater fish in general. HappyChem clarified with more detail on several issues related to salt, hardness, and ph. Roan seemed to think that the reason some people think they should add salt to livebearer water is that they mistakenly believe that it increases water’s hardness. Which she said, and HappyChem confirmed, it does not.... For more on all that see the previous thread .

But the whole thing got me to thinking.... So I looked up some of the sites to see if hardness is the reason that people think they should add salt on a regular basis to livebearer/guppy tanks. I found several different reasons actually, and a whole lot of sites that didn't give any reason. Here is one site that summarizes several I found..

Sea salt should also be added to your tank water. I use one teaspoon per gallon when I initially set up a tank, then about once a month make a partial water change, adding the same ratio of salt to the new water. Salt increases the ability of water to carry oxygen, helps fish produce good protective slime coats, and adds minerals to the water that fish absorb through their skins. These minerals aid in bone and tissue growth. Salt also provides a hostile environment for fungi and parasites, and so helps prevent disease beyond the natural protection of a good slime coat.
From http://www.aqualink.com/fresh/z1-guppy.html

I didn't know enough chemistry to know if any of these reasons were valid.. I have actually only ever used salt in my guppy tank as a temporary thing in times of disease, so I've never been all that worried about it. But now I am curious. I wondered if anyone in the know could clarify more about these ideas or others on regularly keeping salt in freshwater aquariums (Roan and Happychem especially). One big curiosity for me is, if salt is very bad for fish (and Roan and HappyChem make some good points for why it is bad), where did people get the idea it could do all the stuff stated above.. or that it is a good thing for fish in some other way in the first place?
I assume there was some basic idea that got misunderstood like the hardness thing... but does anyone know? Or is there anyone else in the know who still maintains that is *is* good? Are there any guppy or livebearer breeders about who could give a current breeder perspective? Is it a controversy in that community, or just generally accepted as true?


PS As I reread this I realize that it sounds potentially trollish. I really do not mean to start a big uproar, and if it does that I will delete the thread. I am really just a hopeless academic looking for others with a healthy curiosity and hopefully more knowledge in this area than me.
 
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RTR's salt Article


First of all you probably did open a can of worms, but it needs to be done from time to time for newbies. The above article really spells things out quite well, but I did not take it at face value without a lot of research.

I'll post more later, I'm short on time at the moment. There is no pro-salt argument that cannot be easily dis-proven.

Dave
 
First re: the quote you included:

1. "Salt increases the ability of water to carry oxygen,..." This statement is absolutely false. Pure bullfeathers, made-up from someone's imagination.

2, "helps fish produce good protective slime coats,..." This statement is mistaken, and in that is false as well. Fish have no difficulty producing a slime coat - it is basic to their life. Unless you have added surfactants, solvents, or some such toxic material to your tanks (which will kill the fish anyway), they do not need assistance in producing a normal slime coat. Irritants of any sort, and this can include salt, can imcrease the slime coat as the fish's skin fights the irritation. I do not consider irritating the fish to be a healthful practice. It is another garbage statemnt in other words.

3. "and adds minerals to the water that fish absorb through their skins...." Like the first phrase, this statement is again absolutely false, no only with no basis in reality, but it flies in the face all existing factual data on the fuunction of fish's skin and slime coat. First, fish do not, repeat do not, absorb minerals through their skin/scales and slime coat. That is what those structures are for, to protect the fish from the environment. Do you detect a note of xhitzophrnia betyween this statement and the prior one? That the fish need more than normal slime coat, and the fish are absorbing minerals through their skin and slime coat? That alone should tell you something about the worth of this whole bundle of errors out of someones imagination. Pure bull feathers.

4. "These minerals aid in bone and tissue growth. ..." Yes, that is true. But they do not get into the fish through its skin, so it does not apply. They cannot argue that the fish drink the water and get the minerals from that, as FW fish don't genertally drink.

5. "Salt also provides a hostile environment for fungi and parasites,..." that is the job of a normal slime coat, salted water is not needed.

This is all part of historic aquarium mythology, and is at least all 95-100% false. The tiny kernals of fact embedded in the myth are masked by the Big Lie that is largely the product of imagination, unfettered by any testing or refernce to reality. In short, you are being blatantly lied to, but in fairness, they are just repeating what has been said to them.

For more detail see:

http://www.thepufferforum.com/articles/water/salt.html

HTH

Edit: LOL! Dave beat me to the punch, but I had the time for detail. You get the same ref twice this way.
 
I'll pretty much almost always agree with Daveedka, happychem and RTR: those three pretty much have taught me everything I know about aquaria :D

However, I do want to point out that your article quote specifically says "sea salt". Now, as to whether or not they *really* mean marine salt as opposed to aquarium salt would have some bearing on the argument.

happychem made this comment in the original thread in regards to your article:

"Absorption of minerals? Fish may be a little better equipped for this than other higher beings, since they're emersed in the medium. But generally higher beings are not able to derive significant quantities of nutrients from their surroundings because there are too many cells which are not in contact with the medium - hence circulatory systems. Also, the concentration of these minerals is very low, usually not sufficient to satisfy metabolic needs. This is why we get most of our nutritional requirements through food. However, it may be different for fish because they're bathed in the medium. I'm skeptical about this, but I can't rightly say that it's wrong."

It may be that he took "sea salt" at face value, as did I. However, if the author of the original quote *did*, in fact, mean marine salt, then IMO that puts a different spin on things. To happychem, it may not.

Hopefully happychem can clarify as to whether he was commenting in regards to aquarium salt or sea salt.

Could you possibly clarify what the author meant for us, Hypatia?

Roan
 
I'll try to clarify a little bit on the Sea salt verse marine salt thought since RTR already hit the other points I'd planned to post.

Marine Salt mix id very high calcium and magnesium and also contains heavy quantities of Sodium Chloride. It would to some extent provide some minerals that livebearers find necessary (Or at least desired) The problem with marine salt in a freshwater tank is the ratios. The salt simply isn't needed, The magnesioum is pretty high (although depending on dosage amount that would be controllable) and there are quite a few elements in higher than trace amounts that would only be trace in Freshwater.

Mollies fuel the debate more so than most of the livebearers. In the wild Mollies can be found in a wide range of water from pure Freshwater all the way to full Marine. They are however a freshwater fish, and despite their adaptability the need for salt in the water doesn't exist. To my knowledge there are no commercial molly breeders using brackish or Saltwater, and likewise to my knowledge none use Water with Sodium Chloride added. I am guessing based on past experience with this myth, that those backing up the idea were referring to Sea Salt as we buy at the grocery store. This would be sodium chloride for the most part, and would not resemble brackish or marine conditions anyhow.

Now for how the myth gets fueled.
1st thing is marketing. Doc Wellfish figured out that if they rpint a lael, enough people will read it, and they can sell Table salt for 5-10 times what table salt should cost. That is really good for buisiness.

2nd issue is folks who keep their mollies and swords in very soft water will not see them breed. So they go to an LFS, and meet an employee who doesn't know a molly from a red tailed cat, and that employee remembers reading the salt box when he should have been working. He reccomends salt as necessary to get mollies to breed. So the customer goes home and puts salt in the tank, and suddenly the mollies start breeding. So that person tells everyone they talk to that it took salt to get their mollies to breed. A few more folks try it, and so on and so forth until eeryone who didn't do their own research is saying it takes salt to keep livebearers healthy.

In reality Calcium and magnesium would have done the trick and wouldn't pose the long term risks that salt does. Additionally magnesium and calcium are items we can easily test for and controll in an Aquarium so they are definately easier to manage even if they were no better for the fish.

This all boils down to the aforementioned TDS levels. Mollies thrive in Water with elevated TDS levels. Solids come in many forms in our water, some more natural than others. The fish really need the calcium and magnesium that would be part of their natural water source, the sodium and chloride are not needed and can and will lead to shortened lifespans for these fish.

The next Argument (My favorite) is that all water contains some sodium and chloride so all fish need it added to some extent or another. Firstly lets look at quantities. The Saltiest freshwater Lake in the world is Lake Tanganyika, It has roughly 60 ppm sodium and 30 ppm chloride. This would indicate somewhere in the range of 90 ppm Salt. Salt is 60.663% Sodim and 39.337% chloride, so the number are not far off of the correct ratio for these two elemanets to make salt. For information on the rift lakes check the chart at the bottom of this artilce
Additionally since all water in the world has salt at some level, it would stand to reason that your tap has trace amounts, and definately enough to satisfy the needs of freshwater fish

Now for the crux of the marketing practice. Doc wellfish reccomends 1 tablespoon per 5 gallons of water or essentially 1247 ppm of Salt (Based on average weight of one teaspoon being 8.129g) So if we had Lake Tang Cichlids which by far need the highest levels of any freshwater fish then we would be adding roughly 1157ppm or 12 times too much salt by following the label directions given on the box of Doc Wellfish Freshwater aquarium Salt. Sea Salt as sold at the Grocery store is essentially the same thing, so is table salt, canning salt, rock salt and so on.

So the Crux of the matter is Sodium Chloride addition is not needed for any fish that swims in the world. marine fish require multiple minerals, and specified ratios, brackish fish require Multiple minerals at specified ratios, Freshwater fish require almost no salt whatsoever, but some do require specified minerals at certain ratios to thrive and reproduce.

Products like Cichlid Salts, Will provide specified minerals at correct ratio's, and if you read the label on Cichlid Salts you will find it is a mix of mineral salts with very little or no Sodium chloride.

HTH
Dave
 
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WOW! I really appreciate the calmness, clarity, candor and expertise that have been offered to me on this list! I got so worried when I reread my post that someone would reply back "been there done that, go to this link and shut up" or actually start a flame war, or be insulted that I asked for more input than Roan and Happychem had already graciously provided.... not only didn't any of that happen, but several of you have even attempted to answer the real question of "on what logical basis or purposeful deceit, or whatever did all the misinformation start. Thank you to everyone so far.


Roan Art said:
I'll pretty much almost always agree with Daveedka, happychem and RTR: those three pretty much have taught me everything I know about aquaria :D

However, I do want to point out that your article quote specifically says "sea salt". Now, as to whether or not they *really* mean marine salt as opposed to aquarium salt would have some bearing on the argument.
<snip>
Could you possibly clarify what the author meant for us, Hypatia?
Roan

I’d like to give the author or their sources at least that much credit, but sadly I can’t... Here is the rest of the quote which I'd say makes it clear that he/she did not know the differences between marine/sea salt and table/aquarium salt.

Generally, it's less expensive to purchase sea salt at health food stores, rather than pet shops. Although, the sea salt purchased at a pet shop will have more minerals, it isn't necessary to go to that expense. Be sure never to use table salt, iodized salt, or salt with anti-caking ingredients. Also, do not ever use more salt than recommended, as a larger quantity will chemically "burn" your fish to death. Sometimes, large quantities of salt are used for a short period of time to cure specific diseases, but never used on a regular basis.
 
daveedka said:
I'll try to clarify a little bit on the Sea salt verse marine salt thought since RTR already hit the other points I'd planned to post.

Marine Salt mix id very high calcium and magnesium and also contains heavy quantities of Sodium Chloride. It would to some extent provide some minerals that livebearers find necessary (Or at least desired) The problem with marine salt in a freshwater tank is the ratios. The salt simply isn't needed, The magnesium is pretty high (although depending on dosage amount that would be controllable) and there are quite a few elements in higher than trace amounts that would only be trace in Freshwater.

So, I can see that even Marine salt would be bad for freshwater fish for the reasons you and others describe. However, I remember Roan saying earlier that Calcium and Magnesium are a big part of the very minerals that all freshwater fish need, and what species that like "hard water" need more of.

So, if all those parts are accurate (and again, I am only going on what you guys have told me, given I don't know much about this myself) then I think we may have gotten at the answer to my primary question... becuase knowing these two parts, it makes MUCH more sense how hobbyist ever began to believe that adding salt is necessary for livebearers.

If the original person (or people) who made the suggestion actually said to add *marine* salt, they would have been right about getting the minerals that are good for hardness into livebearer water, even though they were obviously still wrong that this is a good solution to soft water, given that the high Sodium that comes with the good minerals is bad for the fish AND the Ca and Mg are in the wrong proportions.
But then, in this scenario, people who didn't really understand the logic behind the marine salt recommendation in the first place keep recommending salt, but eventually the marine part of the words “sea salt” got left out of the picture. That is easy to imagine given how uncommon (and prohibitively expensive) salt water aquariums (and the equipment for such) were in the not so distant past, and how likely it is that someone would have happened upon “sea salt” on their local health food store’s shelves. So then these health food store frequenting people start telling everyone “hey you don’t have to spend so much, because you can get the same thing at the health food store”. And eventually the people perpetuating this silly idea, don't even remember the "Sea" part of the "Sea Salt" reccomendation anymore, because they notice that the ingrediants in their healthfood store bottle are the same as, say, rock salt... and on and on like this, until we are all just going out and buying anything without anti-caking agents, and someone even begans to market plain salt directly to hobbists... Sound Plausible?


TorturedSOUL said:
Is that a picture of you in your avatar? If so, you're easy on the eyes.
Okay, so I know I shouldn’t encourage OT discussions and I am very happily married, but I actually just finished a nine month battle with breat cancer, and I am just now getting my hair back.... and the truth is... I really don’t not feel so “easy on the eyes” these days :o . So even though it has nothing to do with aquariums, I really did appreciate your compliment. My avatar is actually a bellydance picture of me, that I cropped for this site (because I thought it looked very friendly and joyous). You can see the rest of the picture and my public BD promotional site here

Now back to your regularly scheduled aquarium related programming...
 
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Hey, now that all that is resolved, I have another question....

What does all this mean when one is considering using salt as a medication?

This time my question is not just academic, because I think one of my diamond tetras is showing signs of ick. As I was preparing to do my usual routine, I realised there may be more info I need about the salt thing and I am worried that agian critical parts of the picture were left out or distorted of the treatment salt explantions. I have read very detailed scientific explantions of why it works beyond the incorrect slime coat beneift claim, but if I consider all the info you guys have given on this thread.. I think you are saying salt is NEVER helpful in the freshwater aquarium.. right?

TIA
 
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