Planted Tank Guru
Join Date: Jul 2010
Location: British Columbia, Canada
Yes, quite correct.
But to be successful with discus-keeping, no amount of plants, no matter how substantial in volume, will completely rid your tank of the inevitable daily build-up of fish wastes, left-over food, decomposing plant matter, and other detritus, which in turn will serve only to generate more ammonia and nitrites that are the source of developing toxicity - more than can be handled by the plants - thereby negatively affecting water quality & conditions.
The plants will not offset this, and only relatively frequent fresh clean water changes of some significant volume, coupled with a good tank cleansing regimen through vacuuming, tank wipe-downs, and filter maintenance, will accomplish this and maintain high quality water conditions.
The answer to keeping discus healthy & thriving lies with proper husbandry imo & e, and all I'm saying is that a large availability of plant matter is no substitute, nor compensation, for significantly lessening wcs and cleansing, and that's been shown to be valid time & time again.
But hey, it's your set-up, and if you feel it will work well for you, then by all means do so.