How does salinity work for freshwater tanks?

FishForums.net Pet of the Month
šŸ¶ POTM Poll is Open! šŸ¦Ž Click here to Vote! šŸ°

Kyanite14

Fish Fanatic
Joined
Jan 12, 2023
Messages
147
Reaction score
48
Location
USA
I want to raise the salinity so that the water is 1%, since I read this may slow down the progression of columnaris enough to wait for the antibiotics to arrive in the mail.

Problem is I have zero idea of how salt works. I donā€™t know how much to add to make it ā€œ1%ā€ or how that translates to the parts per thousand thing in the online calculators.

I added what the API salt suggested, 1 tbsp per 5 gallons, but what does that raise it to?

Is someone able to explain this?
 
Last edited:
There are devices for measuring, but if you order one it'll probably arrive after the antibiotics anyway. I bought one to check the water in molly habitats in Honduras, and kept it in case I ever get a brackish tank. But everyone starts out treatments with different water, and while I hope one of our resident chemists can give you a formula, I think you've done what you can and now you have to wait.

1 tbsp per 5 is a solid dose. What you are doing is making it hard for the bacteria to spread and grow, so for a holding pattern it's a smart approach. As for exact readings, sit back and hang in. I doubt you'll get one. But you have taken a good run at the Flexibacter infection with what you're doing.
 
1% salinity is easier to work out in metric. It's 1 gram salt in 100 grams water ie 100 ml water. So 10 grams in 1000 grams/mls ie 1 litre.
That sounds like an awful lot of salt.

I have just weighed some table salt and 1 heaped tablespoon weight 25 grams. 5 gallons is 19 litres. So that 1 tablespoon (25 grams) in 5 gallons is the same as 1.3 grams per litre.

I'd be scared to use 10 grams per litre - 1% - in a freshwater tank.
 
1% salinity is easier to work out in metric. It's 1 gram salt in 100 grams water ie 100 ml water. So 10 grams in 1000 grams/mls ie 1 litre.
That sounds like an awful lot of salt.

I have just weighed some table salt and 1 heaped tablespoon weight 25 grams. 5 gallons is 19 litres. So that 1 tablespoon (25 grams) in 5 gallons is the same as 1.3 grams per litre.

I'd be scared to use 10 grams per litre - 1% - in a freshwater tank.
Ah yeahā€¦ I think Iā€™ll just wait until the medicine arrives then. It said 1% kills columnaris but if itā€™s that high then Iā€™ll just hope the amount I have is enough to slow it.

Not really wanting to transition into a saltwater tank šŸ˜…
 
The most important part of the below is the last sentence.

Mainous, M.E., Kuhn, D.D. and Smith, S.A., 2012. Efficacy of common aquaculture compounds for disinfection of Flavobacterium columnare and F. psychrophilum. Journal of Applied Aquaculture, 24(3), pp.262-270.

Abstract
Flavobacterium columnare and F. psychrophilum are important pathogens of the aquaculture industry, and thus disinfection of aquaculture systems and equipment is essential for disease control. This study examined commercially available compounds in vitro for their ability to eliminate these two species of Flavobacterium from the water. The compounds evaluated included Clorox, ethanol, Roccal, Lysol, iodine, formalin, Chloramine-T, glutaraldehyde, potassium permanganate, sodium chloride, and Virkon Aquatic. In this study, 70% ethanol, 50% ethanol, Clorox, Roccal, Lysol, iodine, glutaraldehyde, Chloramine-T, and Virkon Aquatic reduced the number of bacteria of both species to zero within one minute of contact time. Formalin and 30% ethanol also killed both species of bacteria, but required a longer contact time. Potassium permanganate killed F. columnare within one minute, but did not reduce the numbers of F. psychrophilum even after one hour of contact time. Sodium chloride was not effective.
from https://www.tandfonline.com/doi/abs/10.1080/10454438.2012.708291

However, I can also post research that the amount of salt you are using can work well as a dip. "Nine groups were treated with 1.0, 2.0 and 3.0% NaCl for 5, 10 and 30 min each." and "Since short duration sodium chloride bath was found to be effective in the control of columnaris disease, 1% salt disinfection of fry and fingerling stock for 30 min could be incorporated into routine management in catfish hatchery"
from https://academicjournals.org/journal/JVMAH/article-full-text-pdf/DB6B1A460224

Most bacteria dislike cooler temps. This why operating rooms are so cold. So if you can lower the temp. that whould do something to slow the bacteria until you get the meds. However, you should not lower it below the lowest acceptable temp. for whatever species you keep which has the highest low temp. range.
 
Last edited:
So 1% salt is OK as a dip but not to add to the tank?
 
@Kyanite14 to your initial question, it is at best a risk and at worst a detriment to use any "medication" on fish that do not have need of it meaning an obvious disease/health issue that needs treatment. As for salt, depending upon the species this is almost always detrimental when being added regularly and not for a specific issue that needs it. Soft water species are especially vulnerable to salt being present in the tank on a long-term/permanent basis. The salt makes it much harder for the fish to carry out necessary life functions, weakening them and making them more susceptible to this and that. More info in my article.

 
What fish are you treating?
Are you sure they have Columnaris?

If you only have guppies you can add 4 heaped tablespoons of salt per 20 litres and they will be fine for a month in that. Other types of fish like tetras won't tolerate that level of salt. But if they have Columnaris, you need antibiotics.
 
What fish are you treating?
Are you sure they have Columnaris?

If you only have guppies you can add 4 heaped tablespoons of salt per 20 litres and they will be fine for a month in that. Other types of fish like tetras won't tolerate that level of salt. But if they have Columnaris, you need antibiotics.
What fish are you treating?
Are you sure they have Columnaris?

If you only have guppies you can add 4 heaped tablespoons of salt per 20 litres and they will be fine for a month in that. Other types of fish like tetras won't tolerate that level of salt. But if they have Columnaris, you need antibiotics.
Other people have confirmed it. I ordered antibiotics but they wonā€™t arrive until Thursday, so Iā€™m trying to use salt and low temperatures to slow the progression until then. I have guppies/neons/nerite and the one with columnaris is a dwarf gourami
 
The most important part of the below is the last sentence.

Mainous, M.E., Kuhn, D.D. and Smith, S.A., 2012. Efficacy of common aquaculture compounds for disinfection of Flavobacterium columnare and F. psychrophilum. Journal of Applied Aquaculture, 24(3), pp.262-270.

Abstract
Flavobacterium columnare and F. psychrophilum are important pathogens of the aquaculture industry, and thus disinfection of aquaculture systems and equipment is essential for disease control. This study examined commercially available compounds in vitro for their ability to eliminate these two species of Flavobacterium from the water. The compounds evaluated included Clorox, ethanol, Roccal, Lysol, iodine, formalin, Chloramine-T, glutaraldehyde, potassium permanganate, sodium chloride, and Virkon Aquatic. In this study, 70% ethanol, 50% ethanol, Clorox, Roccal, Lysol, iodine, glutaraldehyde, Chloramine-T, and Virkon Aquatic reduced the number of bacteria of both species to zero within one minute of contact time. Formalin and 30% ethanol also killed both species of bacteria, but required a longer contact time. Potassium permanganate killed F. columnare within one minute, but did not reduce the numbers of F. psychrophilum even after one hour of contact time. Sodium chloride was not effective.
from https://www.tandfonline.com/doi/abs/10.1080/10454438.2012.708291

However, I can also post research that the amount of salt you are using can work well as a dip. "Nine groups were treated with 1.0, 2.0 and 3.0% NaCl for 5, 10 and 30 min each." and "Since short duration sodium chloride bath was found to be effective in the control of columnaris disease, 1% salt disinfection of fry and fingerling stock for 30 min could be incorporated into routine management in catfish hatchery"
from https://academicjournals.org/journal/JVMAH/article-full-text-pdf/DB6B1A460224

Most bacteria dislike cooler temps. This why operating rooms are so cold. So if you can lower the temp. that whould do something to slow the bacteria until you get the meds. However, you should not lower it below the lowest acceptable temp. for whatever species you keep which has the highest low temp. range.
The medicine finally arrived, it was hard to get because it was discontinued by a lot of manufacturers for concerns of cancer. But Iā€™m always careful to wash my hands and keep it out of my eyes/mouth.

He was actually looking a lot better before I added the medication. Still a bit of white on the mouth, but the white on the base of his fin disappeared. I still added it just to get rid of the rest, but I think the low temps and salt really helped him.
 
@Kyanite14 to your initial question, it is at best a risk and at worst a detriment to use any "medication" on fish that do not have need of it meaning an obvious disease/health issue that needs treatment. As for salt, depending upon the species this is almost always detrimental when being added regularly and not for a specific issue that needs it. Soft water species are especially vulnerable to salt being present in the tank on a long-term/permanent basis. The salt makes it much harder for the fish to carry out necessary life functions, weakening them and making them more susceptible to this and that. More info in my article.

I donā€™t use it regularly. Iā€™m just trying to slow the infection until my order arrives. It did today and I added it, Nitrofuranzone Iā€™ve read is the best thing for columnaris. When I do the water changes I wonā€™t add any more salt, and if the infection clears up by then, I wonā€™t add any more medication either.
 

Most reactions

trending

Members online

Back
Top