Epiplatys annulatus

You are right Eric, the Annulatus fry are indeed tiny.
I have used infusoria - particularly Paramecium in the past. Unfortunately I have allowed my cultures to 'lapse' so wouldn't be able to help you with a sztarter. I got the original starter off UK ebay, maybe there is still a seller over there?
Alternatively you could try getting a non-specific Infusoria culture started - in a different age I used to use a small particle of banana skin in water - it goes quite ?: cloudy at first, but once the water starts to clear you should see (with a magnifying glass) tiny creatures within the water. I wouldn't recommend using tap water though - try to collect some from a natural source (ie a lake - you mightn't get too close to a river just at the moment). If you start a culture going now it should be ready by the time the eggs start to hatch.
Your suggestion to use a sponge filter could work, but I have, personally, never used it with any Killies. I have used the egglayers Liquifry with limited success, but the fry always seem to get a better start to life when able to get living foods right from the 'off'.

Good luck with them.

John

I am thinking that rain water - being basically (naturally) distilled water would not have anything in it to begin the infusoria culture where water from a river, lake or even a pond would contain a tiny amount of the spores to get things under way.
But these things seem to be a constituent of airborne dust - so perhaps if you have a source of rain water which has been standing for any length of time it might well have enough in to get things started.
Colin (Puddlefish) did a short article on Paramecium culture in (of all places) the 'Articles' section - that makes for interesting reading too.

John