FishNoob wrote:
In my tank, there are two sailfin mollies, two black mollies and one
silver molly. There are also three fry of varying sizes, all black,
with the largest having some pale-coloured patches on its abdomen.

I know one of the fry came home from the LFS, but I don't know where
the other two came from. I've been assuming that one of the mollies
in the tank arrived pregnant, but most websites seem to say that a
pregnant molly is very *visibly* pregnant - i.e. it's not something
you'd miss - and I've not noticed any of mine looking pregnant. Is
pregnancy in a molly always unmissable? And could fry born at the
same time in the same tank grow at different rates so that they are
now quite different in size?

(It just occurred to me that maybe the largest is a male? - I'll have
to wait for it to come out and see if I can tell.)

One of the black mollies is male, one female. The male has a much
larger dorsal fin than the female. Is this a characteristic of
gender, or is it something he's acquired through breeding? When he
flares it, his dorsal fin looks almost as impressive as the male
sailfin's dorsal fin.

Behaviour - today I've noticed that the male black molly is being
very aggressive with the female black molly - prodding her to the
extent that he's actually knocked her over sometimes. He's pushing at
her just behind her anal fin. She's taken to hiding down near the
bottom of the back of the tank, which made hubby suggest that maybe
she was giving birth, but I wonder if she's just trying to get some
peace from the male LOL. She looks plumpish, but certainly doesn't
have the "almost square from the front" appearance I've seen
described on websites.

If we do get more fry (and from today's reading I think it's almost
inevitable, and yes, I can see a larger tank in my future LOL), I
know we should use a breeding trap of some kind. What kind is best? -
the nets which allow the water to flow through? - the solid perspex
kind? - the specific breeding ones that let the fry fall through into
a separate compartment from the mother? And when should I move the
mother-to-be? I know it should be as late in the pregnancy as
possible, but is there any particular kind of behaviour I should look
for?

I am really liking this fish-keeping business by the way :-)


The first thing to realise is this is just the start....Mollies plus
water equal lots of Mollies....with your first born you will do anything
to raise them (yep I have a breeder trap I no longer use) - eventually
you get overrun with fry...start believing in survival of the fittest -
I know it sounds mean but what else are you going to do with them - you
might get a bit of credit for them if you can grow them to a decent size
but that means a major investment in tanks and time....I know this
sounds mean but been there and done it....I love having the babies but
the ones that are kept now are the ones that can survive in the
tank...plenty of plants and hiding places...I've recently gained 3
rapidly growing platys in my largest community tank - the rainbows keep
trying but the Clown Loaches keep saying "lunch" - lol

Right, to give you an example of the problems with fry....look at
this....I have an African Malawi tank...the fish are at it like
rabbits...they have overstocked themselves to the degree that nitrites
are rising (put in a Fluval 4 plus to go with the Fluval 304 tonight to
attempt to control it). I am doing twice weekly 20% changes just to keep
life under control. And two days ago one of my Yellow Labs released at
least 5 that I can see which means there are more - these fish are still
only around a year old - as they mature their capacity to breed
increases....I need to take in the fish for credit and have been offered
20% of sale price if I can grow them big enough and they aren't mutts
(well known problem with Mbunas) but some of them I know for sure are
pure breds.....

Mollies, Platys or in fact any livebearers are so easy to breed there is
no market for them....I've traded mine for Otos (when I hit it lucky and
it was around 30 of them) or merely a thermometer....

But yeah, it is great to know that you have created an environment where
your fish feel happy enough to breed - nothing can take that away...In
spite of what I have just said I love watching my Mbuna's interracting
at all levels with the fry, juvs, almost adults and the real grown ups...

Fish breeding and growing up in your tanks to adult hood are part of the
pleasure of keeping them.....all I have found is that a little realism
of the scale of the probelm can quite quickly overwhelm you.....eg. my
Mbunas.

Really, what I am saying, is let your fish breed, give plenty of cover
for the fry to survive (unless you want to do it commercially you will
never cope with doing it properly - ie. breeder tanks, grow out tanks
etc). You will get the pleasure of raising some of them without being
overwelmed and you might also get some credit when you trade them
in....(fish food, new tanks etc cost a lot)...

I am so happy you are settling in to this hobby. Research and questions
show that a passion rather than a passing phase.....I'm alreay a sad
muppet with this and don't really have as much to offer as some of the
more experienced on this group....

Gill