Mollys won't breed

[TheCountryGoldfish]

how do I know if my Mollys don't like the male or males that I put in there I've had them for like 4 months now in a 40g breeder plz help to try to eventually make a profit but currently they are just being weird.

 

[CaptainBarnicles]

Molly males don't care if the females don't like them, they will fertilise them anyway!

Stupid questions incoming, unfortunately one we find ourselves having to ask...are you sure you have males and females? And are they in hard water?

Posting pictures of your tank and fish may help us to work out why you're having trouble?

 

[10 Tanks]

Hello. What is your water change routine? Mollies are the most particular of all the live bearing fish as far as their water conditions are concerned. Unless the tank water is near nitrogen free, these fish will not breed. The temperature has to be between 78 and 82 degrees. That's not much "wiggle room". They also need a pretty specific diet. Algae is a staple for them.

10 Tanks (Now 11)

 

[TwoTankAmin]

My experience with livebearers was only with swordtails, mostly the Montezumae. But a lot of the livebearers are similar in their mating habits. Here is what one of my go to sites has to say about breeding Poecilia sphenops aka Short-finned Molly/Black Molly.

Very easy if the correct water conditions are provided. Reproduces in standard livebearer fashion. As with other species the males can be somewhat incessant in their pursuit of females so we recommend that several females should be kept to every male in order to dissipate this. Areas of dense planting will also help. Gestation takes around 8 weeks and large broods of up to 120 fry are not uncommon. The adult fish will predate on the young so the best method of raising them is to remove the gravid female to a separate tank and allow her to give birth there before returning her to the main aquarium. The use of breeding nets or traps is not recommended as their small size is not suitable for raising fry. The fry are quite large and will accept brine shrimp nauplii or powdered flake from birth.

from https://www.seriouslyfish.com/species/poecilia-sphenops/

They also say this:

A planted tank is preferable but this species must be maintained in moderately hard or harder water, with a basic pH. When kept in soft or acidic water, the fish weakens fairly rapidly, frequently indicated by shimmying, fungus, and/or clamped fins. Salt is not necessary, as it is the “hard” minerals (calcium, magnesium) that are crucial to the long-term health of this species.

If you need to make your water harder, I can recommend Equilibrium by SeaChem.

Also, in case you are keeping Poecilia latipinna aka Sailfin Molly, they need similar conditions. You can read their page on the above site here: https://www.seriouslyfish.com/species/poecilia-latipinna/

 

[Naughts]

Molly males don't care if the females don't like them, they will fertilise them anyway!

Stupid questions incoming, unfortunately one we find ourselves having to ask...are you sure you have males and females? And are they in hard water?

Posting pictures of your tank and fish may help us to work out why you're having trouble?

I also wonder if there is a mix of mollies and platys? Mollies are bigger and longer, platys smaller and rounder. They are sometimes mis-sold. They can't cross breed.

 

[emeraldking]

Let's make one thing clear about livebearers. It's the female which will decide wether she allows a male to mate with her or not no matter how often and how long a male is chasing her and directs his gonopodium to the female's vent. So yes, females can be choosy and males on the other hand don't care what kind of female they'll chase.
When the situation is like a dislike of the female towards the male, that's a normal thing and any other attempt to get them mated will be effortless. But yes, a water change might get them in the mood to mate but if she doesn't like the male, no mating will take place.

If she's ready to mate, she'll releases a scent from her vent. The male will put his mouth close to her vent from below. That's the sign that it's okay. And the male can approach her from the side or from below to direct his gonopodium to her vent.

 

[CaptainBarnicles]

Let's make one thing clear about livebearers. It's the female which will decide wether she allows a male to mate with her or not no matter how often and how long a male is chasing her and directs his gonopodium to the female's vent.....

if she doesn't like the male, no mating will take place.

I stand corrected!

 

[Colin_T]

If your mollies aren't breeding/ producing young, deworm them. See section 3 of the following link.

What to do if your fish has Stringy White Poop.

Fish do a stringy white poop for several reasons. 1) Internal Bacterial Infections causes the fish to stop eating, swell up like a balloon, breath heavily at the surface or near a filter outlet, do stringy white poop, and die within 24-48 hours of showing these symptoms. This cannot normally be...

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