Hello. Can anyone diagnose what's happening with this echinodorus plant leaf.It has tiny holes which is surrounded by a dark film. My water parameters are ammonia 0/ nitrate 0/ nitrate 10ppm. Phosphate is 3ppm. Light runs for 8hrs with a 1 hour ramp up/down.100% power approx 3 hrs. I use root tabs every 6 wks, liquid potassium 10ml 3x aweek liquid iron 5ml 3x per week, tnc complete 10ml 3x aweek. C02 runs at 2bps. Starts up 1hr before light comes,an finishes 1hr before light shuts down. Everything else is thriving.