Z
Since you have a Discus tank and are good about Water changes, this will be easy.
For lighting: try a 2x 54 watt T5 set up.
That's a nice amount of light for the tank.
I would build two nice piles of drift wood on either side of the tank asymmetrically with a nice off center path leading to the back.
I'd suggest adding Narrow leaf java fern all over the wood and Anubias, Bolbitus etc.
You can use white sand in the foreground if you wish and use something like the ADA aqua soil substrate in the rear(3x9 liter bags will do well).
This will make the tank look nice and be easy to care for as well as be nice for the fish.
I'd suggest using CO2.
It's easy to use.
The KH is bit high for some fish, but if they are fine, stay with it.
It's a little less than 8 degrees.
Go to the pH/KH/CO2 chart and follow down what pH is needed to get 30ppm and add enough CO2 to get that pH.
Do not do anything else to change pH, other than use CO2, that's what the plants.
You can do this for a WC routine, 2x a week, 40-50%, and dose the nutrients thereafter(2x a week).
Add after each water change:
3/4 teaspoon KNO3
1/8 tsp or a tad more of KH2PO4
TMG: 15 mls 2-3x a week
That's all there is to the routine at this point.
Pack the tank full with plants when you plant the tank.
The CO2 and light upgrade will really help and make the layout and care really easy and very nice plant growth.
You can sell Bolbitus and narrow leaf java fern for lots of $$$ on aquabid to off set cost.
Regards,
Tom Barr
Tank is 75 gals, no CO2, NO3 is at best 5ppm, can't go more than 5 days without pwc, discus tank requires regular pwc's. No ammonia or nitrite. PO4 is .25ppm, ph is 7.6 ppm, Kh is 140, gh is 80mg/l (don't know the conversion). Tank is not near sunlight, 9 discus, 3 cories and 2 clown loaches, been set up for a year. 60 wattso of bulbs in total on the tank so that would be .8 WPG right? Did I forget anything, I can take iron and calcuim tests if need be.