Your Aponogeton
OK. The variety from Madagascar is Aponogeton "boivinianus". If you have it planted with a few other plants, then it will get fairly tall, in excess of 16 inches. A young plant will grow fast and then slow down with age.
The bulb is the food source, so I think you're safe trimming some leaves close to the bulb. Just remember that this plant grows in spurts and then slows and loses leaves, so it would be good to trim on the conservative side. You don't want to trim too much and be left will a semi naked bulb in your tank.
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