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Fish/are my mollie about to drop fry?


QUESTION: Hello all, hope you're doing good ;-)m

I have the following question about my pregnant mollie.

Ok,,she has been with a male mollie from day one we bought her, and in that same day the male started to insemenate her.  Its been 3 weeks since then, and this morning I've noticed that she's acting strange, like trying to avoid the male, turning her body in a "s" shape.  So I've desided to place her in a breeding net, just for incase she might start dropping fry.

Since this afternoon she's been making strange moves for example, going into the plants of the breeding net, moving her body into a "s" like shape, swimming up and down then just staying still, her fin are downwards, and she's moving back and forth and side to side. What can this be?? I'm really worried that she may die!!!

Michelle :-)

ANSWER: Hello there!

She's seems perfectly active for a molly I honestly wouldn't worry about death!

What you should be worried about is that breeder net and how long you are keeping her in there! Nets are very small and do not provide the ample space Molly fish need to swim. Nets also stunt the growth of the fry (fish babies), stunting basically means their insides keep growing and growing but their physical bodies do not.

Breeder Boxes are better suited, they float around the aquarium and at least provide space to both the mother and the fry.

Does she have pregnancy signs? Rotund belly, gravid spot (head of fry), decreased activity levels, enlarged or dilating vulva? By the three weeks she should already have late signs of pregnancy, gestation period is only 30-60 days, perhaps 90 but that would be very rare.

She should only be put in the breeder box for short peirods of time, 3-6 hours at most, and then gently taken out. When she is in the box you'll need to turn off the aquarium lights, this reduces stress and gives the female a little nudge to start dropping the fry.

I am stressing about stress because if the female gets stressed out she will abort the babies or she will give premature birth or simply drop dead or very weak fry.

So this means when you are replacing and placing her in the box you shouldn't chase crazily all over the aquarium with the net, in late pregnancy she should be very easy to catch as their energy is reduced.

If she does show signs of pregnancy she probably isn't dropping because of the stress and the limited space a net only provides.

Also some advice would be to feed her protein foods or high nutrional value foods so the fry and the mother will be strong during and after birth. Frozen Brine Shrimp and Bloodworms are good examples.

The babies will need high protein valued foods until they are juveniles (2 inches at most) which is frozen crushed brine shrimp or freeze dried blood worms. Hikari also sells First-Bites and Micro Pellets that will ensure the health of your fry. I use both the product's for all of my fry.

I hope your female gives birth to strong and healthy fry!

---------- FOLLOW-UP ----------

pregnant mollie
pregnant mollie  
QUESTION: Hello again and thank you so much for your answer, it helped me allot,,,the breading net that my mollie is in are quite big,,,the floating box are much smaller cause its for my pregnant guppies ;-). I do have allot of diffrent kind of fish in my tank like swordtails, platties, balloon mollies, sailfin mollie and guppies. I just love my little swiming children.  The thing is, all my female fish are pregnant, and the reason why I keep the mollie in the breeding net is because of the males that won't leave her allone and keep insemenating her,,,she has swim arround the whole day to get rid of them, and I think this is stressing her out,,,she's quite calm in this morning in the breeding net, tummy a bit bigger and the vulvu do have a opening and I see 2 dots there.  I feed her high quality food and bottom feeder pellets. She loves to eat them, she's still making the same movements but not as fast as last night.  Most of the time she's hiding at the plants or at the bottom of the net. Her breathing is fast and her tummy are darker than yesterday. My 2 female guppies that are also in their breeding box are really dark at the vulva area, and I also see 2 dots there, and their tummies are round.  Then my 2 babie fry guppies are now 3 weeks old, I keep them seperate in their own breeding net, they are doing great and growing by the day. I have a 60 liter tank. I will sent you some pics then it will be easier for you to see.


ANSWER: I am going to be blunt with you a bit here but isn't that a aquarium a little bit overstocked?

I understand that this is off subject from your question but Sailfin Mollies get HUGE around 5-6 inches and they need at the least a 30 gallon aquarium. Regular Mollies, Platys, and Swordtails also need 20+ gallons. It sounds that you dearly care for your fish, depending on the quantity of fish and the fry you decide to keep, I would consider upgrading your aquarium size if you get the oppritunity. This is also might be the cause of the slightly cloudy water. I hope I am not nagging at you too much.

To show you an example of a large sailfin molly, this is my big white sailfin in one of my 35g's, at 4.5 inches. At the moment he is pushing 5.5 inches with a 2 inch high sail.(By the way those two golden mollies are my homebred ones!)

Back on subject! It might as well be another week before she drops the fry. Try darkening the aquarium to help her and the guppies out. She seems on the brink of labor. Depending on female/male ratio they will harass her to no end. If she's the only female in the aquarium every time the fish believe she isn't pregnant they'll start inseminating. With every male molly you should have 3 females. This goes especially with sailfin mollies who, get much larger in size, can hurt other molly fish quite easily.

---------- FOLLOW-UP ----------

my sailfin male
my sailfin male  

my male plattie
my male plattie  
QUESTION: Hello. Thank you for you honest answer about the tank, I do realize how big they all get, I've looked it up on the internet.  But yes I will be upgrading my tank asap, or I will get another one so that I kan keep all the small fish in one and the big ones in the other one. Toghether with the algea eater I have 26 fish, and this is without the baies, I will sell the babies, depending on how beautifull they are, most of my fish are still small and that worries me allot,,because of the sailfin, but his really a gorgeous fish!! I've been keeping the tank dark for 2 days now and feeding the mommies 2 be twice daily. They are much more relaxed now,,thank you for all your help,,,in liters how much is a 30 gallon tank? We work in liters.

That is a beautiful sailfin! I love his colors! He seems to have a nice large black sail. If he is the father to the fry the fry will turn out to be nice sailfin calico's, a great mix.

What algae eater do you have? Common Pleco's get 3 feet long and need a 100+ aquarium. Chinese Algae Eater get 1 foot long and will kill most all fish once they reach adult stage. Bristlenose Pleco's AKA Dwarf Pleco's get 6 inches and need a 30-40 + aquarium as they get semi-aggressive as well. All of them have very high bio-loads.

If you can I would consider a 170 litres or higher with 26 fish especially because you might possibly have an aggressive bottom feeder.

In East Asia where I live we use the metric system all the time:

45 US gallons = 170 litres
30 US gallons = 113-115 litres

With a larger aquarium you'll see much clearer water, larger and healthier fish, and less aggression on the female fish.


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Ash WolFF


My knowledge of fish ranges from freshwater and saltwater fish compatibility and care from easy livebearers to monster fish. I can help you set up a simple freshwater aquarium to a complicated reef tank. I would be pleased to assist anyone who is new to the aquarium hobby.


I have been in the aquarium hobby for eight years mostly dealing with large and small aquariums. I keep mostly monster fish (Arowana's, Large Cichlids; Oscars, and freshwater/saltwater eels specifically) but now that I am in college I am keeping a 30 gallon tropical community and a 45 gallon brackish aquarium while my father tends to the big monsters I left behind.

I'm on YouTube! My 30 gallon community posts are the only ones that are up so far. My Brackish tank is next! I'm on Yahoo Answers:

I am currently in college aiming for a job in Marine Biology.

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