R help - Nov 2013 - ODE does not reach steady state and increase exponentially

Dear all,
please follow the link to the question that I posted on StackOverflow about
my R code with ODE
http://stackoverflow.com/questions/20218065/ode-does-not-reach-steady-state-and-increase-exponentially

I am trying to write a code for a differential equation that should give me
the biomass of different size classes, depending on the amount of available
food. Nevertheless the biomass does not reach steady state, and increases
exponentially even with parameters set to 0 (which in theory should result
in a biomass value of 0)

Thank you very much for your help!
I appreciate it

Matteo
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