What size is your tank Lewjo and what filtration do you have ?
How much water can you age and change once weekly in % ?
You should keep no less than 5 discus, prefferably same age and size ,and they should be full grown if you want to keep them in a community tank with just one WC per week .
Other than that I would change the fake plants with natural and the nein tetras with cardinal tetras , since they are more temp. tolerant and a bit larger than neons.
Good luck and take your time to plan things right before you take your next step.