I've had a very large and healthy Amazon Sword in my tank for about 3 months now. Other than the occasional leaf becoming discolored and me pruning it off, I've had no issues. However, within the past week or so I've been losing healthy, large looking leaves almost every other day. They appear to be brown and rotted at the base but they still have a nice vibrant green and are fairly large. I also use root tabs once a month and liquid fert weekly. I also just recently stopped using small doseges of liquid CO2 daily but I dont see how that could cause such a large issue. Any ideas on what's happening?