Thinking of trying to breed them

So I'm thinking of trying to breed discus and was wondering about a few things. For filteration would a sponge filter would be the best? How would a power filter work? For the substrate, why is it best to have not to have any? Would I be able to get 6 discus to pair off in a 29 gallon? Also, does anybody know of any good sites where I can get discus?

No one?

HI killer.
I am in sydney australia so I do not know were to get discus where u are but as to breeding, I have found a small 2ft by 2ft tank with a cone and sponge filter and heater is what you need, changing water frequently to start breeding is the best about 10-20 percent 2nd daily and once a week about 50-80% to shock them into spawning. I often found after a super big clean where you think it would but the off from breeding it did the oposite.
please message you if you have any more questions. the net is a great place to find things but a friend who is doing it is a great help.
les