great, thank you. I never paid too much attention to the eggs but I'll check it out tonight. I do know that they go from a bright orange color to a brownish color through time. I never tried to breed them, but they do lay eggs quite often. Might be an interesting project to try.How are they not hatching? Do the eggs develop/have eyes in them after a few days? If not, sounds like the male isn't doing his part of the job, but if they are growing, the male is tending to the eggs, and they just disappear overnight I would say they are hatching and becoming food in the tank quickly.
If you want to make them strictly a breeding pair, a 20G with a clay flower pot is all you need for the parents to be full time breeders. If you want to keep the clowns in the display (like me, as I really don't want to become a full time fish breeder), you just have to watch and see how many days it takes for the eggs to hatch, normally 9-11 days (mine hatch on day 10). Once you figure out the day they hatch, as soon as the lights go out on that day turn off your powerheads/pumps and all lights in the room so it is pitch dark, wait 1 hour, then shine a flashlight on the surface to see if the babies hatched. If they have, use a turkey baster or tubing to suck them out and put them into their own tank (5-10G is fine for the first month) with live rotifers, an airstone, and a heater. Live rotifers are the key, without them I don't know anyone that can get the babies to live past day 4. Reed Mariculture sells a million rotifers for $20 that you then grow out in 5G buckets so you have a steady supply (only need them for the first 2 weeks, but they are also good coral food). The total for my order was around $75 for rotifers, 32oz of RGFeast to feed them, and shipping (which is 1/2 the cost).
Are you sure they are all gone? Maybe there is a little one and we can name him Nemo!