This is my discus tank.
It has a Duplamat 20 substrate heating cable.
The substrate is a mix of silver sand, laterite and Dennerle Duponit mix. This is covered in a layer of black quartz gravel.
This seems to work well for the plants, and the correct substrate setup can make all the difference (see first few pictures for growth rate).
It is filtered by a biolife 55 wet/dry filter, which will be replaced with an external when the juvenile discus grow.
I only use re-mineralised R.O. water for this tank, not only does it keep the pH and alkalinity low for the discus, it also has less than 5% of the pollution found in tap water. This also helps the plants, as well as reducing the amount of maintenance needed.
The tank is lit by a LifeGlo (high intensity white) and a Trocal plant light, set for 10 hours.
I also make good use of plant root tablets and liquid plant foods, also essential for the plant growth. If the plants grow well they also use up a lot of the waste from the aquarium water.
It houses a variety of small shrimp species, as well as some small Hara cats, some bumble bee gobies and a few kuhlis. A shoal of darter tetras, trifaciatus pencils and some eye spot rasboras. I have a shoal of H. notatus for algae eating.
It holds a pair of show quality leopard discus, and a pair of pigeon blood discus. I will be adding another pair soon.