Finally took the time to unpot the anthuriums that were looking diseased. Had to get rid one of the plants already.. I should’ve checked the root system before I did that. Anyway, I found out what the problem was.
Plants are often grown in turf.. so the base of the plant is still in that little piece of turf. I bet it’s helpfull for the plant to grow in turf or it is cheap for the company that grew the plants. Anyway.. it is really dense and compact and eventually will smother the plant. It doesn’t let air through, it probably stays drained too long after watering the plant because it is so closed. I bet it is like a sponge, at least that is what it feels like. So eventually the base of the plant will start to rot. It doesn’t leave room for the roots to grow from the base of the plant because the turf is in the way. The roots that try anyway end up rotting so I had to cut those away. It was difficult to peel out the turf from out of the base but I bet that the plants feel better without it. It might be possible that the turf even becomes toxic because it becomes a sponge type of texture so the waste that comes from the plant will stay in the turf instead of leaving the soil with the water.
Also I gave them a slightly bigger pot so that they have a bit of room left to grow healthy roots in. On the bottom of the new pots I’ve put a layer of hydrograins that helps with drainage. Of course the pots have holes in it as well but the hydrograins will help the water go through faster. I filled the pot up with anthurium soil and left a bit of space in the pot, I think the base of the plant shouldn’t be covered to avoid crown rot because of wet soil. Also the air roots should be above the soil as well.
My recommendation now with new plants from the store.. best to repot them immediately to see how the roots are doing and remove the turf from the plant base. With orchids I do this too but after the plant stopped blooming.