¿How should I configure a trench simulation?

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Hello all. I'm exploring CROCO and I'd like to describe physical processes into a trench, so I need to perform a trench domain simulation. Many parameters are defined in crocotools_param.m in order to smoothing the batimetry, like rtarget = 0.25, n_filter_deep_topo = 4, n_filter_final=2 (also I would need to define hmax = 8000;). How do you recommend to configure CROCO in order to run a trench simulation (about 8000 m) with very steep slope?, it is possible to consider a realistic batimetry without experiment numerical problems or so?