Planted Tank Guru
Join Date: Jul 2010
Location: British Columbia, Canada
There is no question that generally speaking, discus will do better in a bare-bottom tank - they will likely grow more quickly, and more readily achieve their best growth potential in terms of size. A BB tank will permit more pristine tank cleansing and therefore allow maintenance of higher quality water conditions.
A planted tank will more than likely result in slower growth of the fish and a larger ratio of less than optimum-sized fish.
Having said that, there is nothing wrong with keeping discus in a planted environment - it just takes more care and attention in maintaining good water quality and a very clean tank environment. One simply needs to give the fish ample swimming room, in a just lightly to medium-planted set-up, to permit effective waste clean up of the substrate.
It also requires regular, large water changes, and careful attention to maintaining a relatively low bio-load of stock vs. tank size, more so than in a BB tank, along with ample filtration.
I've kept discus in several planted tanks over the past 5 years or so, with very satisfactory results - but I recognize that it takes more work to keep tank conditions squeaky clean - which I have been prepared to do.
Hope this helps.