I have a pair of Discus that spawn regularly, they are in a tank by themselves, bare bottom, with one potted sword and a flowerpot for egg laying. No problems with laying or fertilizing and I have witnessed this on several occasions. The problem is, when the eggs are less than half a day away from hatching, they are eaten. The hours prior to this both parents look after them. I shifted the tank to a spare room, incase there was too much activity around them, same thing happened, I have taken the male out and left the female with the eggs, again the same thing occured. Water parameters are perfect for breeding, and there is only a handful of unfertilized eggs with each batch, which are picked off by them early on. The female is between 12-18months,and I have tried changing the male, so one male is 4 years and the other 12 months. This has been happening 3-4 times a month for the last six months. I used to keep the same water changing routine going while the eggs were there, but for the last few months, I stopped all percieved interferance, so the water remained unchanged for the 2-3 days the eggs were there. Still don't even get to the wriggler stage! Any ideas would be appreciated