Marc i want you to read this. This is from the other forum i am in and there was a debate on can mollies live in
FW when i asked a ? about platys and this is what they said
QUOTE(blitztidus @ Feb 28 2006, 05:39 PM)
That is a common misconception on mollies as they can strive in BRACKISH or FRESHWATER, I have mollies in my 100% no-salt tank.
That's the common misconception, actually. Mollies don't do so well in freshwater. Sure, they can live in it, just like you could probably live in a closet your whole life, but it wouldn't be the best for you, or make you the healthiest. If you are going to keep Mollies in freshwater, it needs to be hard and alkaline. That's the kind they prefer. If it's soft and acidic, that's when you really need to add salt. Wild type Sailfins and Black Mollies are the ones that just need it, however, almost all Mollies are hybridised so it's virtually impossible to look at them and say "You need salt!". It's best to keep all of them in a bit of salt, to make them the healthiest and happiest they can be. In pure freshwater, they are much more susceptible to disease, especially shimmies, and they don't tend to live as long. Salt is the way to go with these guys. BY: Anastasia
Mollies might just cope without salt if you have very hard alkaline water, but I have very sad memories of trying to keep them in soft, acid water- just one round of
ICH after another. Platies seem a lot more adaptable. By: Dwarf Gourami
It's even more complex than this.
There are a number of species of molly (as opposed to varieties), some of which are exclusively freshwater, while others usually brackish, and a few species inhabit either. Poecilia salvatoris, known as the liberty molly in the hobby, is purely a freshwater species. Poecilia orri, the mangrove molly, on the other hand, is much more a brackish water species. Poecilia formosa, the Amazon molly, is found in both brackish and fresh water.
The complication comes from the fact that none of the mollies traded commercially are pure species. While we (hobbyists) use names like Poecilia sphenops and Poecilia velifera all the time, the sad fact is these species have all been hybridised for decades by breeders to produce all the artificial forms. So for any one variety, like a black molly or orange sailfin molly, you have absolutely no idea what the genetic heritage of the fish is, and it wil include genes from many different molly species, some familiar, others not so.
The result is that fish you buy might have mostly brackish fish genes, or freshwater genes, or a mixture of both. Some people are lucky with them in freshwater, and I use the word 'lucky' deliberately, because they get fish that mostly have freshwater genes and so work out in freshwater aquaria.
The majority of specimens seem to have at least some brackish genes, so on balance, as Annastasia says, keeping mollies in brackish water makes sense. The freshwater species aren't harmed by salt at all, and the brackish water species need it, so if you keep artifical varieties of molly with some freshwater genes and some brackish water ones, adding salt works out as a safe choice.
Regardless of the
salinity, what hasn't been mentioned is
pH and hardness. All mollies need hard, alkaline water, which is exactly what common aquarium fish like neons and dwarf gouramis don't want (or tolerate). Adding marine salt mix to the water raises both pH and hardness very effectively, and hence does double duty, creating both the right salinity and the right water chemistry.
It should be added that most livebearers, if not quite all, will thrive in slightly brackish water. While platies and swords don't need salt, they will do fine at specific gravities below 1.005, and guppies can be adapted to anything up to marine conditions (though you need to do this carefully). In the wild most livebearers inhabit brackish water in some part of their range, and this is one reason that they quickly become pest species when introduced into other parts of the world: unlike most other
freshwater fish, they tolerate brackish and marine water, and so can distribute themselves along coastlines very effectively.
Cheers,
Neale
Commercial molly breeders raise them in brackish water, period. So the idea they're "used to freshwater" isn't really tenable. As Annastasia says, while they will do well in freshwater, they do better in brackish. Black mollies in particular do astonishingly well in fully marine conditions, and they are often used to run-in new marine tanks because of this.
If your mollies are fine in freshwater, it's almost certainly because you have hard, alkaline water. When the pH is 7.5 or more, then mollies tend to do okay in freshwater. As soon as you try to keep them in neutral, or God forbid, acid water conditions, that's when they "get the shimmies". And fin rot. And fungus. By: neale again
If you are going to keep Mollies in freshwater, it needs to be hard and alkaline. That's the kind they prefer. If it's soft and acidic, that's when you really need to add salt as otherwise, they are so much more susceptible to disease, especially shimmies.
Blitzdus - As I said before, it's possible for them to live in freshwater, just like you can live in a closet. You certainly wouldn't be your happiest or healthiest though, would you? As Neale said, your water must be hard and alkaline, otherwise you'd be seeing a lot more disease with them. Anyway, I'm not trying to argue, but I feel this needs to be said as Mollies are just regarded as Freshwater or Brackish, depending on who you talk to, with no regards to water conditions. by: annastasiia
Annastasia, I'd perhaps add a third thing to this debate, swimming space. In my experience, and from what others tell me, mollies are more sensitive to overcrowding that any of the other common livebearers. Sailfin mollies in particular really need at least a 60 cm, 20 gallon, tank, and if you're going to keep a trio, then surely a 90 cm, 30 gallon, tank is the minimum?
I've been told that male baby mollies will only develop their sail fins if given plenty of space. The more crowded they are, the more stunted they get. Certainly, I'm of the opinion that while cranking out mediocre mollies is easy, producing good quality fish is not easy, and of all the livebearers, mollies are the ones that demand the most from their keepers.
Having said that, I love mollies. I wrote a piece for PFK a few months back with "5 almost perfect fish" as the theme. The black molly was number 1. For me, the wonderful dark colour really stands out in a planted tank, and few fish seem to have such sweet personalities and lively dispositions. Mollies are excellent aquarium fish, it's a shame we tend not to treat them all that well.
Cheers,
Neale
Mollies can live in freshwater, as mentioned, if it's hard and alkaline, but then the Cories won't work as they prefer soft, acidic to neutral. by: annastisia
tell me now what you think of having mollies and corys together and tell me what you are going to do with your tank now that you have read this
p.s. the people who wrote this gave me there permission to do this and they want you to stop by if you have any ? Marc and if you do PM me and i will give you the link to that forum
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