Hi @BrynZA ,
Welcome! Please read and understand the User Guide before using InVEST. Then, search this forum for answers to your questions before posting new ones. Related posted include these:
Varying the DEM between 30m and 90m resolution versions without changing the threshold flow accumulation (TFA) value will drastically impact export estimates. As stated in the User Guide, TFA
directly affects the expression of hydrologic connectivity and the sediment export result: when a flow path reaches the stream, sediment trapping stops and the sediment exported is assumed to reach the catchment outlet. It is important to choose this value carefully, so modeled streams come as close to reality as possible.
Also be sure to read about TFA and the DEM.
Have you compared and validated your modeled stream networks with real-world stream maps or imagery?
-Jesse