Hi again.
I would not use egg yolk fry food, as you say – it will pollute the water. And they wont take it I am pretty sure about that.
Once the fry is out of the cave, and once they themselves have no more eggyolk – you will loose sight of them totally. Which means you will not be able to target any feeding. They will dissappear into some of the dense areas of the tank, most likely at the bottom in the beginning, – they will also of course be hiding from other fish, so they are really invisible for probably about a month or two months.
And then … where to add food ?? :dry:
So in my opinion one needs to cultivate these infusorias and add to the tank, – and I dont think you need to worry about polluting the tank or other fish, even theres quite a big amount of infusoria.
After about a week or so, you can already start adding things like microworms, and if you feed the other fish with artemis nauplia theres also a chance that the fry will feed on the tiniest of these.
So I would feed infusoria for about a week, then move to if possible, vineager ells or microworm for a week or two, then leave it to only be artemia – or of course you can change between these, but infusoria is only important in the very very beginning – they will move to other type food quick.
The tank size is okay, not overly too big. – and why dont you as calm as possible, when over the next days you have the chance, just net out one fish at the time and move the adults.. leave the cave and the male and move the other fish ? I think theres a better chance then.