Hi beckyd:
When I came home after four days away, I had two new parents and a sword-like plant leaf covered in eggs, with the two angels taking turns either going berserk on any other fish coming near or blowing on the eggs/picking carefully through them, I'm guessing discarding damaged eggs, detritus or fungus. I wasn't prepared at all, and within the next twelve hours the eggs started to wriggle, which I now understand means they were about to hatch. By then it was New Year's Day, and almost every store was closed, but I managed to find one random fish store (which I now kinda like - they have a crazy selection of fish beyond the LFS I have been using, and their tanks are pristine. There is a bit of a language barrier though . . . ) Anyway that day I was able to buy a 5g, **sponge filter** (answer to your question), heater and a plastic cover (I have cats, so can't keep an open tank) plus some frozen brine shrimp, and transfered the leaf to the 5g. Quite a few of the 'wrigglers' fell off the leaf in the transfer (maybe I did it a wee bit too late in the hatching process) but I didn't notice that those were the ones to eventually perish. I did lose about half the fry. By the time I learned that A: I really needed live brine shrimp, and B: how to hatch them (I have a method now) I'm sure my fry were pretty challenged. However, the 23 or so that I still have are eating beautifully, growing quickly, and it's becoming much, much easier to clean the bottom of the tank as the fry are easier to spot and don't hang so low to the bottom all the time now. But yes, it's been a LOT of work!
I think that your pic #2 of the angel's papilla looks like the female, but it's hard to tell with a pic. What I have observed while the papilla on both angels is apparent is the female's is wider and blunter while the male's is pointier (makes sense, when you think about the biology, no?). Anyway, if your breeding pair are still displaying their papillas, you should be able to see a clear difference. Just try to remember the markings of each, because once the papillas disappear, you won't be able to tell!