Hi Amadeo. Welcome to this wonderfull place. Where do you live ? You can complete your profile data so folks here can help and give advise better.
I dont know if peace lily need that many ingredients in their pot. I have about ten pots of peace lily and i only mix garden soil and compost mixture on 2:1 ratio when repotting them. And they look happy to me.
Some people say that they need to put some gravel or pieces of broken clay pot at the bottom of media to improve drainage. But i am not sure if it really work.
Thats my humble opinion. Wish other advance gardener here will give you better advise soon.
