one more thing, heres some info on neon tetra eggs:
"Each female can lay up to 130 eggs each time . However hatching rate is low , at least in our facilities. Eggs normally hatch in 24 hours in our climatic conditions. The larvae become free swimming in about 5 days."
and here is zebra danio info:
"The spawning looks almost violent with large quantities of eggs (up to 200 from a mature female) being laid in the plants. Java moss, artificial spawning mops, and pots and wood (they spawn in the crack between the object and the gravel) are favored places to leave the eggs. Because danios eat all of the eggs and fry that they can reach, to get young, you must either remove the parents after spawning or collect the fry. Eggs hatch in one to two days. After birth, the fry attach themselves to the glass for a few days. his makes them very prone to being eaten by any fish in the tank."
and here is just plain old egg info:
" For egg scatterers, eggs look like tiny clear balls that stick to whatever they landed on, including each other. For labyrinth fish, the eggs are very tiny, clear balls suspended in the bubble nest. With egg depositors, the eggs are usually larger and stuck on some surface. Cory catfish often stick their large eggs on glass and plants, and some species have colored eggs. Look into what the eggs look like for each species in the tank to determine which one laid the eggs. After a day, black spots should appear at the center of each egg that was fertilized. Later (a few days), you should be able to discern a pair of eyes looking at you if they are indeed fish eggs. Snail eggs will usually be in clumps on surfaces either in or out of water (depends on species), and amphibian eggs will usually not be stuck to anything but each other or perhaps anchored to a plant. If you still cannot decide what laid the eggs or debris, put them in a small container or tank of water at the same temperature and pH as the main tank or pond and wait. Check daily to see if something is growing in the "eggs." If they are fish eggs, the eyes of the fry inside the egg should be obvious as hatching nears. If after two weeks, nothing has been born, then you will never know if they were good eggs that died, unfertilized eggs, or just some debris."
hope this helps!