I would still advise some sort of aeration other than just the plants, most plants will oxygenate the water as a bi-product of photosynthesis, however this is only when its light, in the dark many plants will actually suck O2 back out of the water and those water lilys O2 from being absorbed from the air just by taking up water surface area.
gold fish eggs are tiny and sticky, the parents will spawn onto plants and the eggs should not get sucked up by a filter unless the plants get really stirred up, the babys however are tiny to start with and can easily get sucked up, Elodia like Joanne has is one of the best spawning/ nursery plants.