Sailfin Molly - Any Info Please

[scuba_jez]

hey i bought a sailfin molly to replace my late gourami. my tank is 9 gallons or so with a couple of corys already in there.

his body is about 2 inches long and the bloke at the shop said they wouldnt get much bigger than what they are already... sooooo

does anyone have any info about these? ive tried googling and looking at the fish index but theres really not much on them.

thanks

 

[Annastasia]

Sailfins can get to 6", so your LFS didn't have the correct info.... He isn't going to be able to live in a 9 gallon, he's going to need at least a 20 gallon to get to his full size. Do you have any tanks that are bigger then the 9 gallon?

Other then the size, they are basically like other Mollies except they can be more aggressive. Sailfins usually do like some salt in their water. But you need to make sure you have salt-compatible fish in with him.

Also, Mollies have slightly more complex feeding needs then other livebearers. I suggest you look at Toxis-Phoenix's post in this post, as it explains it very well.

Good luck!

 

[nmonks]

Hello Annastasia, scuba_jez,

At least in the UK, adult size depends a bit on the sailfin molly being sold. From my experience of tropical fish stores in Nebraska, the situation in the US isn't all that different. As far as I can tell, almost all the "green sailfin mollies" sold in England are Poecilia latipinna, and these don't get so large. In the wild, big females are around 10 cm long, males about 2/3rds that. Only very rarely do you see the "Mexican sailfin molly", Poecilia velifera, which, as you correctly say, has the potential to get much larger.

However, such stock as is available of either species is heavily hybridised and/or stunted by poor conditions, and rarely do you see even the biggest females of either species get to their full size. I've been told that male mollies are even more sensitive, and if kept as juveniles (fry) in cramped quarters they never fully develop their sailfin. In short, you really want to try and get your hands on wild-caught stock if you want to see these fish are their best.

That said, both species are at least relatively easy to keep. The saltier the water, the less problematical they are, and there's a good argument to be made for simply calling them brackish water fish and leaving it at that. I wouldn't ever keep them in a freshwater tank unless the pH was at least 7.5 and the hardness "very hard". Such conditions are obvious inimical to things like gouramis, tetras and barbs, but would be fine for rainbowfish, guppies, dwarf halfbeaks, gobies, and so on.

Diet is simplified the more vegetables and algae you offer; they definitely cannot do well on regular (carnivore) flake alone. They also need relatively high temperatures, I'd recommend upwards of 25 C.

One last thing: these are schooling fish, and a single male in a 9 gallon tank is only just short of cruelty. I'd suggest keeping a male and 2-3 females in a 30 gallin tank as being a good start, and there'd be a little room left over for some gobies and halfbeaks.

Cheers,

Neale

Sailfins can get to 6", so your LFS didn't have the correct info...

 

[Annastasia]

Hi Neale,

Sources all say different things. As you said, basically it depends on the species. Where I live, almost all the Sailfins you see for sale are 5-6". I was just stating the maximum size, since scuba_jez did not specify the species. It's best to plan for the biggest size, just in case you get a fish that big.

 

[nmonks]

Hi Annastasia,

Honest, I wasn't trying to be a no-it-all!

As you say, depends on the species, and whether you get the sailfin molly that grows to 10 cm or 15 cm, a 9 gallon tank is way too small. I mean, I use a 10 gallon to raise halfbeak fry in, and even they bump their noses occasionally! Since mollies are sociable fish, I'd think it a wee bit cruel to keep less than 3 specimens in a tank, and that's going to any your aquarium size/filter issues.

Wish we got the 15 cm sailfin mollies here. Only ever seen genuine, wild-caught fish once, about 12 years ago. Otherwise, it's always the "regular" sized green sailfin molly, and pretty mediocre mass-produced hybrid stock at that. I chatted with a local fish store manager about this topic a few weeks back, and he commented that 'plain' mollies just don't sell: all the plebs want is the brightly coloured artifical forms. Me, I'm old fashioned, and like my fish au naturel.

Cheers,

Neale

Hi Neale,

Sources all say different things. As you said, basically it depends on the species. Where I live, almost all the Sailfins you see for sale are 5-6". I was just stating the maximum size, since scuba_jez did not specify the species. It's best to plan for the biggest size, just in case you get a fish that big.