Well Kings, there's good news, and not so good news.
My best advice to new discus-keepers wanting to ensure they are successful at it, is to keep it as simple as you can to begin with, don't overcomplicate things, and keep your TLC focus fully on the discus, not your plants, aquascaping, etc.
It can be a lot easier for those aquarists who have a good amount of previous experience with fish-keeping in planted environments, but that's still not a guarantee of success.
A heavily planted hich-tech tank with pressurized CO2 can certainly make things more problematic in properly caring for discus. While reasonable, daily pH swings are not abnormal in any tank, and are acceptable in keeping discus, so long as they are gradual over the day and night, and not overly large in terms of the pH level, any quickly changing pH can and usually will be a problem. Similarly, a high nitrate level is usually harmful to discus.
EI or other fert dosing should not pose a particular problem, nor should reasonable other carbon source (e.g. Excel) dosing.
To start off properly with discus, I would suggest avoiding a high-tech, pressurized C02 environment until one has gained several months' experience keeping discus.
As for keeping them in planted tanks, I have done so many times with good success, but I do religiously undertake large, frequent wcs, and follow a strict, meticulous routine of tank & filter media cleansing, with frequent tank wipe-downs, vacuuming, etc.
It certainly can be done successfully, but there's no doubt it takes more work and attention to say, a bb tank, and it often may tend to limit the growth and development of discus to their optimal potential.
Hope this helps.
You may want to have a look at my planted discus tank, where I've been raising juvies for many months. I know full well some may not reach their full growth potential, but as long as they're happy and healthy, I'm fine with that.
Anything more I can do to help, don't hesitate to ask.
Best of luck to you.