Discus, like most fish, can adapt to a broad parameter of water conditions. What you need is clean stable water. It’s best you don’t mess around with the water parameters, especially since you’ll need to be doing large and frequent water changes if you plan to keep discus and not stunt them.
A breeding pair should be kept in soft acidic water to give you a higher chance of success with the eggs.
That being said, you’ve been given good advice. If you want to keep discus in a planted tank, you would be better off buying adults. It’s not clean enough in a planted tank to grow out discus without stunting them. Besides, if you end up doing huge water changes to do right by your baby discus, you’ll be stripping the water of nutrients that are beneficial for plants.
To grow out dinner plate sized discus, you need to be putting them in a bare tank with very clean water, lots of water changes, and good quality food. By lots of water changes, I mean that even doing large daily water changes wouldn’t be out of the question.
This doesn’t mean you can’t keep juvenile discus alive and growing in a planted tank, it just means the likelihood of them getting stunted and you being disappointed is very high. They’ll get bigger but won’t ever reach plate size. This is why you should buy adults to start with and put them in your planted show tank. Growing out discus to full size is not easy
