Are mollies killers?

[cichlid]

My dad's swordtail (male) was killed along with a platy.the only fish i ve seen aggressive tiwards other is the mollies.

[Lady Hobbs]

Is the tank cycled?

[cichlid]

yep,my other fish r fine we have 2 tetras (need more so they can school) 1 swordtail, 2 mollies, and 1 platy in a 20gallon

[Jacko]

It could easily have been the mollies, I've had bad experience with them and platies before, they used to beat up on the platies.

It could also have been something completely different. Do you know your water parameters? Those would be helpful in finding out why they died.

[cichlid]

I saw injuries on both fish so I think its them 2

[Jacko]

those could be wounds from after they died, fish are scavengers and any of them will take advantage of a dead body in the tank.

You might want to look into what your parameters are.

[cichlid]

but the swordtail was alve when I saw hiw wounds i came bcak home to see the platy dead

[jono]

Mollies have a taste for slime coat on other fish. My sailfin has knocked out 2 of my balloon mollies.

[geowashlaw]

Our molly and our platy are the docile ones in our tank ... the guppies and tetras pick on both of them all the time ...

[terrapin24h]

my platies and guppies are unquestionably the tank wimps. Fortunately, my 3 spot gourami has taken a shine to them and protects them. Otherwise, i wouldn't be surprised if my snails could beat them up ;)

--chris

[Naturestee]

How is your tank set up? Plants, rocks, hiding places, etc? And how big is it? Maybe there's not enough space?

My mollies are the most gentle fish in my (29 g) tank. The male sometimes flares at the platies but he's never actually gone after them. Usually all three mollies are busy grazing on algae all day. It might help that my tank has a lot of plants, including a thick forest of hornwort, plus some rock caves.