Thanks for all the nice comments.
This tank was setup around the late 90's. There has been many changes in plants, equipment and maintenance.
As of today the lighting are four 40 watts daylight fluorescent T12 bulbs in two Shoplight lamps from Home Depot. They are on with a timer for eight hours. There are a lot of plants floating in the surface so the light doesn't reach the bottom of the tank in some places.
The filter is a fluval 305 and the output is connected to a spraybar which is underwater and covering all the back of the tank from side to side. There is only the foam blocks and baskets are full of ceramic rings, no carbon or chemical filtration. On the right there is a hagen 402 powerhead with a quick filter and a spraybar from right to left.
The gravel is river sand with Tetra Intial Stiks in the bottom not available anymore. Temperature around 80-84F and PH 6.5.
I use reverse osmosis water with Seachem RO Right to add minerals. For fertilization I use Seachem Flourish 5ml weekly. Water changes are done twice a month more or less 10 gallon.
My fish only eat OSI Discus Food, no frozen or pellets.
I think that the key to success on this type of plated aquariums is:
Tank FULL of plants from the beginning
No splash in the surface or air bubbles that remove Co2
Limited feeding and not too many fish
A lot of luck
I am very bad at plant names but i think I have:
Onion plant (long leaves covers must of the surface)
Water hedge (some floating in the surface)