I recently purchased a VFT that is developing black areas on the leaves and traps and then the leaf dies. There is no evidence of spider mites or anything else I can see. I treated it with an insecticidal soap to be sure, but to no avail. The plant is in a sunny and humid location here in Florida and I have tried altering the amount of sun it gets thinking that maybe that is the cause, but again this has not made any change. It is planted in a 4" plastic pot with sphagnum substrate that is kept moist and it sits above a pebble tray of water. I only use distilled water and never have added any fertilizer. New growths have appeared, but then turn balck and die. This is the second time this has happened with as many plants. The first one I killed was all green, this one is green and red. Before I give up and discontinue killing these are there any suggestions? Thank you.