Molly and Platy pregnant-will fry need filtration, are my plans ok?

I have 2 female baloon mollies and 2 twinbar platys, male and female. One of my baloon mollies was purchased pregnant, and my male platy has now impregnanted the female. So both will be having fry before long. The baloon molly is much further along than the platy, I'm expecting withing a few days, and I have her set aside in a net breeeder.

I would like to know if, a couple days after the fry arrive, if it would be acceptable to put them in a spare 2L tank I have sitting around. I plan to fill it with water from the main tank. There would not be filtration in the fry tank, so I plan to do partial water changes with the main tank daily. Would this be acceptable?

Also, assuming that the platys come soon enough that the molly fry are not significantly larger, would it be okay to use this same process with my platy (net breeder then into the 2L with the molly fry)?

Thanks in advance for any help you can provide.

Thanks for visiting our forum.

Moving fry from an established aquarium to a new setup will shock them, and they may not survive. Using water from the main aquarium will help, but you would also need the beneficial bacteria that live mostly in the substrate and filter media. If you get a sponge type filter and let it mature in an established aquarium, you may be able to safely move that and the water into the new aquarium along with the fry. The option that works best for me is a dense bunch of a floating plants like hornwort or water sprite. Fry naturally head to the water surface as soon as they are expelled, and the dense, floating plants protect them from hungry adults.

Lots of people use net breeders, but they're pretty confining, and the female fish can turn around and eat her fry.

Wow, the platy must be much further along than I had realized. She, too, must have been already pregnant when purchased. I can now see that little pink dot, and with a very close look at her fairly translucent body, I can even see what appear to be tiny fry eyes in the abdomen between the pectoral and anal fins (correct terms?).

Can anyone take a guess at when I should be expecting, how long I have to wait?

Actually, that wasn't entirely acurate. I thought I had read something about a pink spot prudtruding from the, uh, birthing canal (?) sometime shortly before birth, but when I went back to find that information, I couldn't relocate it. So I could be wrong in that aspect, though there is still a very small pinkish thing protuding from just below the gravid spot. Does this mean anything?

The gravid spot is quite dark, with some red in and above it. There is even more dark above the red, but she is relatively transparent, so mabe this is just organs? In any case, this whole area forms a sort of semi-circle, with the rounded end facing the dorsal fin. The two sections of dark make a V-like shape, with a redder color in the middle, and some tiny bits of the red within the dark. There are also what appear to be fry eyes, surrounded by faint outlines-the head itself, perhaps?

With all that, I am assuming she is due quite soon, except that she isn't super big, just slightly plump. However, I have never breed platys before, and mollies only once years ago, so I'm not entirely sure.

Does anyone now have any ideas as to when she may drop the fry?