What’s the science behind adding salt?

[Barry Tetra]

Yeah, I was wondering, why do we have to add them? Especially with medication.
Does it help with the healing of wound or like those Hospital Saline thing people use???

can anyone do a scientific explanation to this?

 

[kwi]

Salt Uses In Freshwater Aquariums

I realize that the use of salts in freshwater tanks is a debated topic but that is not my purpose in posting this today. I simply want to clarify the confusion that many are having in using salt for freshwater fish. Below are some guides that I hope will help those of you that are interested...

www.fishforums.net

 

[mbsqw1d]

It effectively dries out bacteria/fungus/parasites via osmosis. So, as the water balances itself out across the semi permeable membrane, water is 'sucked' out of the organisms.

 

[Barry Tetra]

It effectively dries out bacteria/fungus/parasites via osmosis. So, as the water balances itself out across the semi permeable membrane, water is 'sucked' out of the organisms.

That's what my biology teacher told me but I'm not sure if she's right or not.

 

[mbsqw1d]

That's what my biology teacher told me but I'm not sure if she's right or not.

Why not? You can do a fairly simple test yourself with some slices of potato.

 

[FishGuest5123]

Salt also improves gill function, reduces stress, and is a mild astringent.

 

[AbbeysDad]

This article written by Byron should be of value:
Salt in the Freshwater Aquarium

 

[Realpedro]

This article written by Byron should be of value:
Salt in the Freshwater Aquarium

Wow, he is not pro-salt at all.

Quotes from the first paragraph:
"As David A. Lass points out, there is not much therapeutic benefit at those dosages. “Salt serves more to assuage the hobbyist’s need to ‘do something’ for their tropical fish,” he writes. [8] There is absolutely no need to add salt to freshwater aquaria except as a specific treatment, and even here the sensitivity of certain fish species must be kept in mind."

"As the scientific data presented in this summary article indicates, adding salt to a freshwater aquarium on a regular basis will, at best, do nothing of any value at all."

 

[itiwhetu]

The osmotiic effect is the problem with adding salt to a fresh water system it sucks the fluid from the fish making it stressed

 

[seangee]

It effectively dries out bacteria/fungus/parasites via osmosis. So, as the water balances itself out across the semi permeable membrane, water is 'sucked' out of the organisms.

The osmotiic effect is the problem with adding salt to a fresh water system it sucks the fluid from the fish making it stressed

Which is exactly why we all say no more than two weeks and only if necessary. The effect on fish is exactly the same as on bacteria/fungus/parasites. Those things die quicker because they are smaller. As with any treatment or medication we have to weigh up the good it does against the harm.

 

[The Lumpfish Guy]

This is an interesting article on the use of Salt in fish and amphibians, summarising what is currently know, with a lot taken from Farmed Salmon and Tilapia
Wangen, K. (2012). Therapeutic Review: Sodium Chloride. Journal of Exotic Pet Medicine, 21(1), 94–98. doi:10.1053/j.jepm.2011.11.012

It mostly talks about the use of baths for external parasites, which seems to be the only experimental work conducted with ornamentals limited to guppies in this paper:
Schelkle, B., Doetjes, R., & Cable, J. (2011). The salt myth revealed: Treatment of gyrodactylid infections on ornamental guppies, Poecilia reticulata. Aquaculture, 311(1-4), 74-79.

Which is Advocating the use of 25gL-1 short baths over longer periods of treatment with lower concentrations (3 and 7 gL-1).

 

[Munroco]

It's something that used to be common practice, people would routinely add salt to all their tanks. More recently I think the theory that it is beneficial has been mostly debunked. I for one don't use it, particularly as most of my tanks have corydoras in them. While it may be fine for some hard water fish like guppies and more particularly mollies, it isn't so good for scaleless fish.

 

[The Lumpfish Guy]

it isn't so good for scaleless fish.

I can't talk for all scale less fish, but apparently long term baths of about 2-5ppt (Doesn't specify time) for freshwater stingrays is beneficial. (obviously a little specialist and there are different biological processes in elasmobranchs, as they can reduced Na+/K+ ATPase activity when submerged in salt water
Wangen, K. (2012). Therapeutic Review: Sodium Chloride. Journal of Exotic Pet Medicine, 21(1), 94–98. doi:10.1053/j.jepm.2011.11.012

 

[FishGuest5123]

Wow, he is not pro-salt at all.

Quotes from the first paragraph:
"As David A. Lass points out, there is not much therapeutic benefit at those dosages. “Salt serves more to assuage the hobbyist’s need to ‘do something’ for their tropical fish,” he writes. [8] There is absolutely no need to add salt to freshwater aquaria except as a specific treatment, and even here the sensitivity of certain fish species must be kept in mind."

"As the scientific data presented in this summary article indicates, adding salt to a freshwater aquarium on a regular basis will, at best, do nothing of any value at all."

He agrees it’s beneficial for some things. Just no reason to add it all the time which I agree with.

 

[FishGuest5123]

It's something that used to be common practice, people would routinely add salt to all their tanks. More recently I think the theory that it is beneficial has been mostly debunked. I for one don't use it, particularly as most of my tanks have corydoras in them. While it may be fine for some hard water fish like guppies and more particularly mollies, it isn't so good for scaleless fish.

Are you talking about using it regularly? Cories can handle small doses for short periods for treating things like ich or fungus.