Is Salt Vital To A Molly?

[SammySosa93]

Hi, I'm really brand spanking new at keeping fish. Three weeks ago, I went to the pet shop up the street and purchased 2 "guppies", McGee and Jethro. I knew from the start that Jethro was different, but I just attributed it to her being a female and thus being bigger. McGee passed away earlier last week, so I stayed up hours on end researching guppies and how I could give them the best care possible. The more I looked at the pictures,the more I noticed she didn't really match up. When I posted a picture on FB to see if anyone could help me out, someone told me that she's a Molly! I read that Mollies prefer brackish water, but I'm not entirely thrilled about the idea of having to put any salt in my aquarium as I had planned on it being a freshwater tank... Do Molly fish absolutely without a doubt have to have salt in their aquarium?

 

[Chad]

Here's an article that goes into great detail about molly.
 
Since it's so long I will quote the source:
 
Mollies are common in saline habitats, including brackish ditches and lagoons. Some may even be found in marine environments, albeit in very shallow water; for example, around the roots of mangroves or artificial habitats like harbours...
 
The mollies in aquarium shops are hybrids that do well in freshwater — provided other parameters are good, particularly water quality and hardness. Still, wise aquarists will stock the molly aquarium with salt-tolerant plants and tank mates, just in case a little salt is needed for good health.
 
My experience has been that they do much better and live longer with salt. This can make it difficult to keep many plants and many other fish with them as many of both are not at all salt tolerant. As the article points out molly are extremely salt tolerant even being able to be kept in a full marine environment. 
 
That said, I have been able to keep sailfin molly alive in fully freshwater, quite healthy, for a number of years but not so with balloon belly molly. 

 

[BelldandyShanny]

I just read an interesting article in tfh  magazine about this, you should check it out if you can.  Big article on livebearers.

 

[iliveinazoo]

You originally wanted to keep Guppies and they can also be kept in Brackish conditions.  Aim for a maximum of SG1.003@25DegC and there are quite a few plants that you can keep as well. Sg1.003 is approximately 3 tablespoons for every 5 (US)G.

 

[Bjorn_Snow]

I have a 29 gallon saltwater aquarium. With live sand, live rocks, one feather duster tube worm, for snails, 6 hermit crabs,1 emerald crab, 1 chocolate chip starfish, several balloon mollies and a few natural strain sailfin mollies. they have been in there for about a month and they are thriving. I have never seen such quick growth in sailfins. my boyfriend keeps his sail fin Mollies in freshwater with a small amount of aquarium salt and a small amount of marine salt in fully live planted aquariums and they do great. they also do just fine in brackish water. they do not require aquarium salt or marine salt.tonight myself and I just take them from fresh water or breakfast water and put in into the salt water and I have not had any healthy ones die from just dropping them in. I would not advise this though.sorry about any typos, I am using the speech to text feature on my phone and it seems to be acting a little faulty at the moment.

 

[Bjorn_Snow]

I have a 29 gallon saltwater aquarium. With live sand, live rocks, one feather duster tube worm, for snails, 6 hermit crabs,1 emerald crab, 1 chocolate chip starfish, several balloon mollies and a few natural strain sailfin mollies. they have been in there for about a month and they are thriving. I have never seen such quick growth in sailfins. my boyfriend keeps his sail fin Mollies in freshwater with a small amount of aquarium salt and a small amount of marine salt in fully live planted aquariums and they do great. they also do just fine in brackish water. they do not require aquarium salt or marine salt.tonight myself and I just take them from fresh water or breakfast water and put in into the salt water and I have not had any healthy ones die from just dropping them in. I would not advise this though

 

[Byron]

The author of the article that Chad linked, Dr. Neale Monks, is as always bang on.  It is not the salt aspect but the mineral content of the water that is critical for mollies, even more than other livebearers.  The "hard" minerals in moderately hard to hard water is absolutely essential for mollies to remain helathy; in soft water they almost always develop skin problems, fungus, shimmies, etc, and a much shorter lifespan results.  Check the GH of your source water (the website of your municipal water supplier should have this, or they can tell you).  If it needs raising, it is simple enough to do with calcareous substrate sand either in the substrate or the filter.
 
Byron.