Dispelling Some Myths about Adding Salt to FW Aquariums

[DewDropPony]

I am/have been a huge advocate of salt for many years, but not for most of the reasons listed. I love salt as a treatment for Ich. I read over and over that salt is beneficial for all livebearers, but rarely have kept it in my livebearer tanks on a continuous basis. I use it more at a tried and true trusted treatment that I always have on hand in case of an Ich outbreak. I did not know that platies, guppies, and sword tails, are not brackish water fish, and that mollies are just adaptable to it, instead of will not be of utmost health without it.

Great article! Very much needed!

[freshwaterjeff]

Right on. Also, using tap water (dechlorinated of course) in Austin, TX is perfect for Mollies and other "quasi brackish" fish because we naturally have a fair amount salt in our water. I've had 3 mollies, 3 cherry barbs and 3 swordtails for 2 weeks with NO problems. But I thank the guys at Aquatek for their advice and patience.

[trill14n]

Thanks for this info; I was under the impresson that a little salt needed to be added every other water change.

[drgallahad]

Nice Job!!!

[rtaylor22]

I had no idea how misinformed I was.... What is the best way to get rid of the salt I have been adding? Other than my normal water changes and not adding anymore Or is that the best way to avoid any additional stress on my fish. Also, will all the things that my fish have adapted to with the addition of salt be undone with getting rid of salt?

[Northernguy]

rtaylor22 Just stop adding salt!
You can remove it with gravel vacs and water changes.
What type of fish do you have? Most FW fish will do fine once the salt is gone,they may do even better.Getting rid of the salt will have no effect on your cycle.

[Lady Hobbs]

Ok well if this is true,which i do beleive your theories then Pet Smart's people are retards for throwing salt in all there tanks! lmao

Not really! Many fish stores add treatment salt doses to their tanks. It's simply a preventive of Ick. Their fish are being delivered stressed out, crowded and not always in the best condition.

Many say their tanks don't get Ick because they use salt but in reality, just as our tanks don't get Ick who do NOT use salt, it's all due to the stress of fish. It's not because you have salt in the water but because your fish are not stressed out.

In nearly every case of Ick, it's due to adding new fish or due to fish that have been kept in poor condition.

[cliff0114]

Recently there have been a number of threads arise regarding the use of salt in freshwater aquariums. Unfortunately, there are some myths out there regarding the use of salt and exactly what it will do. There are still many that use salt and sing its praises, it is just one more thing that does not need to be used all the time and I'd like to clear up a few of the myths surrounding it. The following statements are not merely the opinion of this hobbyist, they are founded in scientific fact.

1. The first idea that I'd like to deal with is the ideal of "Relief of Osmotic stress." This is an idea that is not entirely a myth, however it is often presented as a blanket statement and that is where the myth arrives. For fish that come from environments that have 0 salt (aka, most captive bred fish) the addition of salt does nothing to relieve osmotic stress, it creates it. For wild caught fish that come from brackish environments or environments where there a trace amount of salt can be found, the addition of a very small amount of salt will help with osmotic stress.

2. Myth number 2 deals specifically with livebearers. Mollies, Platies, Swordtails, and Guppies are often presented as being brackish fish or fish that require salt. This is a completely false idea. Platies, Swordtails, and Guppies are all completely freshwater species. Mollies are not a brackish fish, they are however a euryhaline species. This simply means they can adapt to a wide range of salinities. They key word there is adapt, they do not require salt at all but they can adapt to levels ranging from none all the way to full marine.

3 and 4. The third myth deals with disease prevention and the fourth does right along with it; stress reduction. Again, this is not entirely false but it is still entirely unecessary. Salt allows the fish keeper to keep lower than ideal water quality and it reduces the chances of diesase as a result. However, the idea that it will prevent Ich is not true at all. The logic seems to be, since salt kills free swimming Ich, it will keep it from forming. This is not true, and it has in fact lead to a strain of Ich that is entirely resistant to salt. Ich is a parasite and a very adaptable one at that. Maintaining salt in your system all the time simply allows the Ich to adapt to it and develop an immunity to it. Also in this area, the logic seems to be that salt helps create a thicker slime coat which in turn makes them more disease resistant. This reason has to be the most pointless of all the reasons for using salt. While it is true salt does cause a fish to develop a thicker slimecoat, the development of the thicker slimecoat is a reaction to an irritant in the water, and that irritant is the salt. Irritants in the water are a source of stress, and stress is a cause of disease in fish. So, here is what the addition of salt boils down to in this case: salt irritates fish and creates stress -> fish develops thicker slimecoat in reaction to irritant -> fish becomes more resistant to diesase that results from a stressful situation. At this point, the fishkeeper would be just as far ahead without the addition of salt, because with out the salt, there would be no creation of a stressful situation that the fish needed a defense against. Completely self defeating reason.

5. Another reason some people site for using salt is the addition of electrolytes to the water. While this may be true, the exact same thing is accomplished by simply doing a water change. Again, the addition of salt is a redundant and pointless act in this case. The salt concentration of fish blood is 15-17 parts per thousand. In freshwater the surrounding environment has a much lower salt concentration and therefore the tendency for equilibrium causes the water to diffuse into the bloodstream through the thin gill walls through osmosis. As you raise the salinity of the surrounding environment the rate of osmosis slows down. When you reach concentrations that are equal, osmosis completely stops because equilibrium has been reached. That cessation or slowing down of osmosis slows down the electrolyte intake as well. So, the introduction of extra electrolytes via salt simply makes up for the slower rate of osmosis caused by the salt. Again, self defeating.

6. The final thing I want to deal with here is the idea that Salt allows fish to diffuse more oxygen from the water. This is a completely false idea that simply proves that the advocates of this myth simply do not understand fish physiology. There is evidence that things like copper sulfate, salt, and other slime coat boosters can all cause the exact same problem. A good indication of the oxygen content of your water is the ventilation rate of your fish. If a fish is ventilating very quickly then it is attempting to get extra oxygen, and this happens when there is not enough oxygen in the water, the fish is stressed, or it cannot extract enough oxygen from the water. (Edit: author's amendment).

Dont say based on scientific fact and not back up you theories with proof. anyone can say it is scientific facts about anything.

[cliff0114]

I agree- this should be a sticky. I have not seen such a nice, clear and well put together reason for NOT using salt yet. As I have all salt-sensitive fish anyway, I do not use salt, but this is nevertheless GREAT, scientific information and I learned a FEW new things today!

Scientific? I seen an aquarist posting one side of this topic with nothing backing it up?

[Lady Hobbs]

Cliff

If you do not wish to use salt, then don't. No one will agrue with you about it. But fishkeepers with 40 years of experience also know what they are talking about. Skip this thread if you do not like the information here.

The 3 posts you have written at this site does not qualify you to began a dispute with one of our long time members.