Setting up a cardinal breeding tank

[Doobreef]

Hi everyone, finally got some extra space in my room to set up a little tank and figured might as well try out breeding fish. I hear the Banggai cardinal is easy to breed, but I personally like the Apogon cyanosoma's colorations... This is what I currently have:

-10 gallon tank
-18 watt 50/50 light (keeping it low for less algae)
-Biocube skimmer
-Aquaclear 20 HOB filter with LR rubble and carbon
-50 watt submersible heater
-1-2" substrate (mix of aragonite + crushed coral)
-Few pounds of live rock, with caves and the like
-Breeder trap

There is no water in yet, just what you see above all dry and clean. There are no inverts going in there either (only a pair of cardinals.. maybe snail or 2 lol). I have a few questions to ask you guys:

1) Is a powerhead needed, even if don't plan on having any corals or heavy amounts of live rock? The HOB creates a little bit of flow- is that enough for fish?

2) Is there anything on the aforementioned list that is either useless, redundent, or needs to be replaced? Keep in mind I can't increase tank size (20" max size).

3) Do all cardinals breed the same way? Or are there certain differences between them that are important when deciding which species to breed?

Thanks so far,
Rob

edit: forgot to mention I can probably set up a small fry tank for them to grow in if raising them in a breeder trap is a bad idea..

 

[FMarini]

only banggai's (p. Kauderni) and p. mirifica hold for 21days, otherwise all other apogons release fry around day 7-10 as planktonic fry. They are more difficult than banggais- but still do-able if you have dottyback raising experience

 

[WaffleWalffle22]

I'm no expert, but keep a breeding pair in that 10g tank and strip the fry from the male for he releases them about 20-21 days. If there are 6 or less put them in a large breeder trap. Anything more I'd put in another tank.

 

[Doobreef]

So should I take the fry from the male cardinal after the 21 days are over and he releases them? Or before/during those 21 days, where the male will still have them in his mouth?