Blow up with using salinity tracer (negatif value)

Hello everyone
I have a problem with the model CROCO using the PSOURCE. I put a tracer (salinity of a river) and it becomes negative at a certain moment which is not normal according to me and I get a blow up
Can someone help me solve this problem?

Hi, negative values are commun with river runoff from PSOURCE if using non-monotonic advection and large discharge values. you could try using TS_HADV_WENO5 or BIO_HADV_WENO5 (e.g., for PASSIVE_TRACER). You can also try to spread your river input over multiple grid points if it is too strong. Another option is to uncomment the ramp parameter that multiplies Qbar in subroutine ana_psource (analytical.F); that would give use a gradual increase of discharge …

Hello Mr. Pmarches
Thanks for you answer!
Currently I only use temperature and salinity at PSOURCE points.
Sadly, I just tried what you suggested but the problem does not change. Will it not hesitate to other numerical scheme that deals with these kinds of problem.
My study area is in shallow water (Lagoon scale).
Thanks once yet