Are planted aquariums and discus fish compatible?
NO3 < 10 ppm
Discus are large fish that produce great amount of waste generating high levels of NO3 which should be maintained by large frequent water changes. Regardless of how large water changes are performed, plants will still have enough NO3 left.
Same as NO3
Discus healthy environment can have 5 – 15 ppm of K which is also suitable for plants.
Discus healthy environment can have 2 - 5 ppm of Mg (0.5 - 1.1 dGH) which is also suitable for plants.
Discus healthy environment can have 10 - 20 ppm of Ca (1.4 – 2.8 dGH) which is also suitable for plants.
Any proper KH for discus is suitable for plants.
dGH 0-12 ( breeding success higher--hatch [email protected] lower ranges due to ossification of eggs)
Difficult fish are not usually bred in planted aquariums however growing and keeping discus in 2 – 4 dGH is healthy and also suitable for plants.
pH 5-8 Wild and asian import strains tend to need softer water in long term. European varieties have been bred several generations to thrive in harder water. From neutral to 8 ph.
Plants also can grow in pH of 5 and up to 7, and most up to 8, just as discus.
Atmospheric CO2 to aquarium water equilibrium is about 0.5 – 4.5 ppm CO2. Natural waters can have 15 ppm and more therefore there is no reason to suggest that discus could feel uncomfortable in 10 ppm of CO2 which is suitable for plants under low and medium light energy. Furthermore, plants can offer healthier and more natural way of life for the fish.
TDS ppm or µS - My discus stay between 85-120 ppm TDS.
This is also suitable for plants.
Water changes % - Depends on age of discus.
No amount of proper water changes can harm plants.
Water changes period - Depends on age of discus.
No quantity of proper water changes can harm plants.
Temperature -Depends on age of discus.
I was expecting more information about discus temperature requirements because some cases require quite high temperatures which some plant species may not tolerate but those are usually unnecessary or due to fish sickness. When due to sickness then it should be done in hospital aquariums. Recommended temperatures for healthy discus, Juveniles under 3 inch 86F / 30C, sub-adults 3 - 5 inch 84F / 29C, adults 5.5 + inch 82F / 28C.
Discus can feel comfortable under low and medium light intensities which is also suitable for most plants.
Any natural like light period is also suitable for plants.
As we can see discus fish and most plants are compatible. What I would not recommend is extremes in light intensities, CO2 on - off peak schedules and brute over fertilization. Other than that there is no reason not to have healthy discus with healthy plants.
Thank you for the constructive discussion @Discusluv
Is there anything else to mention?