Change In Molly Fish Behavior | My Aquarium Club

Male Molly Fish engages in bisexual behavior to lure females - NeoGAF
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Now a new study by researchers from University of Frankfurt, France, shows that some less attractive male Atlantic molly fish are bisexual and engage in homosexual behavior so as to attract female fish for copulation.
Help With Molly Behaviour - Badman's Tropical Fish
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Gestation varies somewhat, but is typicallyaround a month. Litter size also varies, and in some cases over ahundred fry have been reported, with bigger females usually producinglarger broods. The reason so few big broods get reported byinexperienced aquarists is that other fish hunt down and eat livebearerfry with remarkable enthusiasm. Sometimes, even the mothers will eattheir own fry. In the wild, the fry would move into very shallow waterwhere the adult mollies (and any predatory fishes) cannot go, so thefemales have never evolved any 'maternal behaviour' towardstheir offspring; as far as the female mollies are concerned, a babymolly is just a meal. The easiest solution is to install masses offloating plants: , , hornwort, orwhatever's handy. The baby fish will hide among the plants, and theaquarist can easily find and remove them to another aquarium where theycan be reared safely. Molly fry grow quickly, but do need plenty offood. Algae-based flake food six times a day is ideal, and there shouldcertainly be some algae-covered stones in the aquarium to let them gosnacking in between their proper meals. Throw in some floating plantstoo, as baby fish generally enjoy a bit of shade and appreciate thesense of security that the availability of hiding places givesthem. Watch for any behavioral changes in your female molly fish
Photo provided by FlickrSo was wondering if I should be worried or is this normal molly fish behavior
Photo provided by FlickrMolly Fish Temperament / Behavior : Peaceful.
Photo provided by Flickr
A Molly is usually included among the first fish for beginner aquarists. Mollies are often kept in community aquariums, but they are known to nip the fins of species with long and delicate fins and can therefore be a bad choice if you wish to keep such species. Some fish with long and flowing fin will be aggressive, or simply large, enough to fend of an irritating Molly, while others will be much stressed by the harassment and sometimes even die from infected wounds.

You can keep a single Molly, but they are more interesting when kept together since you can witness more of their natural behaviour. Mollies will not form schools, but they do develop a strict hierarchy among themselves. The male Molly sporting the most striking colours and largest fins is the alpha Molly. If you keep only one male Molly and several females you will avoid a lot of fighting.

You can choose between to major types of Molly; the Short finned mollies and the Sailfin mollies. The most frequently kept Mollies belong to the Short finned group, a group that include well known species like the Black Molly and Gold-dust Molly. Sailfin Mollies have a very spectacular shape and are much larger than the common Short finned mollies. A Sailfin Molly is also harder to keep since it is more sensitive and require more space. A common Short finned Molly will do well in a 10 gallon quarium, but a Sailfin Molly must be kept in at least 20 gallons of water since it can grow up to 5 inches. All Mollies are Livebearers and unlike many fish species, Livebearers do not deposit eggs. A male Molly will instead fertilize the eggs while they are still inside the body of the female Molly, and the eggs will develop into a fry inside the mother. When the fry is large enough, the female Molly will give birth.

In the wild, the Molly is found in environments influenced by tidal waves. The environment created by a tropical flood or stream emptying into the sea is a typical Molly habitat. This means that your Molly will do much better if you keep it in a brackish aquarium. Mollies are capable of surviving in a fresh water aquarium as well, but will be more vulnerable to diseases. If you want to keep Mollies with other species, it is therefore recommended to choose other tropical species that tolerate a little salt, such as the Platy. 1 or 2 tablespoons of salt for each gallon of water is suitable. You can buy marine aquarium salt in most pet shops and fish stores. Frequent water changes is a must, otherwise salt will build up in the aquarium. Since the Molly is a tropical fish, the water temperature in the aquarium should be kept in the 75-80 F range. Avoid including driftwood in your aquarium decoration, since driftwood makes the pH lower. Mollies require a pH between 7 and 8. More suitable decorations are plants and rocks. When you decorate the aquarium, leave a larger area of open water for the Molly to swim around in.

"Sounds like this molly could be a male. Look at the anal fin (the one closest to the tail underneath). If it fans down it is female. If it is straight like a stick, then it is male. If the molly is female, well there's the reason for the others heightened aggressive behavior and why he'd be at her the moment of introduction. Male livebearer fish can be very aggressive when the thought of breeding comes into play."