my water sprite have been growing very well, every week there's about 10 new stem/leaf grow out, but there's always bits and pieces of the leaf floating on the surface. could it be eaten by shrimps?

dosage:
2ml of potassium and 2ml flourish after every water change.
3 days after water change, i will dose 0.5ml each.
1ml of excel daily.

tanks specification: 2ft x 1ft x 1.5ft
PH: 5.5
GH: 5
TDS: 150
temperature: 24.5 to 25.5
light: lightset 1, 3ft 2x36W PL light 6500k. lightset 2, 3ft 25W T8 light. both daily 12 hrs.
CO2: NIL