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Fresh water fish with small amounts of aquarium salt

6K views 9 replies 5 participants last post by  Crocer 
#1 ·
I know this is a debatable topic, butI was wondering what all of you think are fish that can still thrive? I am just starting back up in the hobby and would like to keep black mollies as well as natural mollies(found a store near me that sells them) but I would like to add one or two other types of non-live bearing fish. I have had succes with keeping plecos, cories and dainos with salt added and it didn't seem to bother them at all even my Amazon sword plants looked better. My tank is a 30 gallon long tank.
Variouse ideas I have had are Mollies with:
-other live bearers
- female betta's
-convict cichlids (Ive read it can be done)
-dragon gobies (only one)
-gouramis.
any thoughts on these Ideas for tank mates?
Other suggetions?
thanks in advanced for any info.
 
#2 ·
As I see you recently joined, may I first welcome you to Tropical Fish Keeping forum.

I along with many other members do not recommend the use of salt in any freshwater aquarium. While livebearers can "tolerate" it, many other fish cannot to varying degrees, and none need it. And while using it previously may not have appeared to have done harm, you cannot know what may have been done internally to the fish. I have researched the topic previously, and will copy my synopsis below which I think will explain the scientific position.

Salt is detrimental to freshwater fish and plants in varying degrees. To understand why, we must understand what salt does in water.

Salt makes the water more dense than the same water without salt. The aquarium contains water. The bodies of fish and plant leaves also contain water [just as we do--we are, what is it, 70-some percent water?]. The water in the aquarium and the water in the fish/plant are separated by a semi-permeable layer which is the cell. Water can pass through this cell. When either body of water is more dense, the other less-dense body of water will pass through the membrane to equalize the water on both sides.

Water is constantly passing through the cells of fish by osmosis in an attempt to equate the water inside the fish (which is more dense) with the water in the aquarium. Put another way, the aquarium water is diluting the fish's body water until they are equal. Freshwater fish regularly excrete this water through respiration and urination. This is the issue behind pH differences as well as salt and other substances. It increases the fish's work--the kidney is used in the case of salt--which also increases the fish's stress in order to maintain their internal stability. Also, the fish tends to produce more mucus especially in the gills; the reason now seems to be due to the irritant property of salt--the fish is trying to get away from it.

I have an interesting measurement for fish. Dr. Stanley Weitzman, who is Emeritus Research Scientist at the Department of Ichthyology of the Smithsonian Institute in Washington and an acknowledged authority on characoid fishes, writes that 100 ppm of salt is the maximum for characins, and there are several species that show considerable stress leading to death at 60 ppm. 100 ppm is equal to .38 of one gram of salt per gallon of water. One level teaspoon holds six grams of salt, so 1 tsp of salt per gallon equates to more than 15 times the tolerable amount. Livebearers have a higher tolerance (mollies sometimes exist in brackish water) so the salt may be safe for them.

Plants: when salt is added to the aquarium water, the water inside the plant cells is less dense so it escapes through the cells. The result is that the plant literally dries out, and will wilt. I've so far been unable to find a measurement of how much salt will be detrimental to plants; all authorities I have found do note that some species are more sensitive than others, and all recommend no salt in planted aquaria.

Now you know why I never recommend salt.
 
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#4 ·
thanks for the info, so I guess I should stick with a live bearer tank, species tank or get some marine salt(and salt guage) and have a brackish setup. Have you or anyone here been able to keep black mollies with out salt?
I did many years ago. And I know there are some members here who do not use salt with mollies. They absolutely do not "need" it. They do need mineral though, and sometimes aquarists get this mixed up and suggest salt. Same goes for rift lake cichlids. It is the calcium and magnesium (the minerals in harder water) that is essential. Depending what comes out of your tap, if it is basic (pH above 7) and medium hard or harder, all livebearers including the beautiful molly will be fine.

Byron.
 
#5 ·
I have mollies only and I have slowly been adding salt (every time I change the water (4 gallons) I add 1 teaspoon of instant ocean sea salt, I think its important to use actual ocean salt instead of just aquarium salt as it has extra minerals that help harden the water)

The mollies really enjoy it (they are more active)

But I also have live plants so I am trying to find a nice balance between the sea salt and the plants, so far I have done 3 water changes in my 30 gallon adding a teaspoon of sea salt each time and so far the plants are fine and the mollies are thriving.

I don't know if it will make a difference or not but I am in experimenting mode.

I was thinking of going brackish and I still might if I can't find a balance that the plants will tolerate.

But of course I am new to keeping mollies and very much still green so take my advice with a grain of salt lol.
 
#6 ·
I use ground limestone in my livebearer tanks. Much better- Raises the Gh, ph, and Kh for the fish (adds minerals), without the severe dehydrating affects and toxicity of salt.

The only reason (IMO) people say mollies need salt, is because they are genetically abnormal fish with weak immune systems. Salt can help, but if the salt level fluctuates I personally guarantee an outbreak of disease, and once you start salt, it's extremely difficult to wean them back onto freshwater.
 
#8 ·
My mollies are all kept without any use of Salt.

I also bought a bunch awhile back from a lady who kept them in brackish waters,
Over a months period I converted then over to no salt as well. not a lick of trouble doing so either.
I do believe the fish actually seemed happier too.

I keep Regular blacks, lyre tails, Sailfins, jumbo's, balloons etc, Vairiety of colors
I can honestly say I get more young then I know what to do with.

My mollies are some of the best mollies around here too.
Just recently I got so pissed off at the sheer numbers of young alone I literally tried to kill a bunch and I'll be dang those suckers just wouldn't die!
I ended up taking a hugh amount to a pet store, and I see my tanks are full of young again!
 
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