I have Cryptocoryne Balansae in my tank but found that they tend to grow too long a leaf. The leaves grew to about 2 feet long. Is there a way of keeping their leaves from growing too long that they obstruct light from other lower plants? Thanks.

Size: 2.5x1.5x1.5 ft tank
Lighting: Matrix 36wattx4
Base: ADA Powersand Special/ ADA Aquasoil
Liquidfert: Brighty K, Step 2, ECA, Green Grow (dosed every 48 hours)
Temp: 26.8C
CO2: Injection 3 bubble/sec
Water Change: weekly 20%
Tank age: 6 months