I keep platys in a 20 gal and 45 gal tank. I use hornwort and driftwood to protect them. Weight down some of the hortwort with some net, rocks, and plastic tie wraps. The hornwort turns into a ball of green reaching to the surface and hides fry well. Next put some driftwood in the tank propped up on a rock an one end. Weight down some more net over the driftwood. The babies swim through the net and hide under the wood, the adults can't get to them. The babies that are not smart enough to hide get eaten, but enough of them learn to survive and you get a good batch from each cycle. I have many generations survive that way. I stopped using fry tanks and nets and let nature take it's course with some help from the habitat I create.
I'll also note, I rarely change the intake on my filters. Most platy fry can swim very fast when they need to and although a few may get sucked up, for the most part the healthy ones can withstand the current of the filter intake. Now, the gravel vac is another issue...
Last edited by satwood; 11-14-2008 at 04:36 PM.