I'm going to be honest, from experience spawning media will grab eggs and can be taken out, but I dont know how many eggs I would have missed. The fry I got was from doing just that, I can see eggs from ricefish and rainbow fish but scarlet badis I have yet to visible hold or see the eggs, I believe they are really tiny eggs.
I would just for a month keep pulling out subwassertang every 3 days. Other tip is in the new hatching tank, squeeze out your tanks filter sponge in it for all the mulm. It will be full of little life and put in some sort of leaf litter.