approximately 2 years...
They have 3 times their age!!
depends on what fish you have.
no
Bernd Degen has written: 'Pr\\' 'Discus in the Community Tank' 'Degen discus book' -- subject(s): Discus (Fish) 'Wild-Caught Discus' 'The Proper Care of Discus' 'The Discus--\\' -- subject(s): Discus (Fish), Pictorial works
You
in what
yes, of course a discus sleeps. Every fish sleeps.
How long have you been breeding this pair of discus? A real young pair might eat the first couple of spawns, and older discus will eat weak fry so they don't get a chance to reproduce. If you've got a pair that's had a few spawns and it still eats them, what's probably happened is they ate the first spawn, decided discus fry taste good and started eating them all. There are two ways to go if this happens--you can put a piece of stainless steel wire mesh (the kind you want is called hardware cloth) in the tank as a divider for the young fish to hide on the other side of, or (this is what I would do) decide the breeding pair you have would be nice pet fish instead, move them to a display tank and get a new breeding pair.
in water
they arent -_-
what any discus eats.
no, discus are very slow moving fish zebras are one of the most active fishes. The zebras would stress the discus so much, they might die. If you want pretty fish that are also small, get cardinal or rummynose tetras.