they should not be too bad with those trates, what are your other parameters,
if everything is in line, then do not worry, turbos die, they fall offf the glass and if they land upside down, they cannot flip over and eventuallly die, one thing i have heard is that a lower salininty can cause them to fall off. i am not too sure of the validity, but we have lost 1 in the last several months, after increaing our salinity. now we keep it about 1.025 and don't hardly loose any
HTH