streamlines

[GeoTuxMan]

I try to show currents from Black Sea on a map with streamlines (with leaflet-velocity).
But all streamlines are same color and the map looks very bad.
The map is here: https://syroco.rmri.ro/earth/index.html
I keep the original layer (Ocean Current -Great Barrier Reef) , to see the diference between layers.
I look forward to any suggestion, idea.
The code from demo.js:

                                          function initDemoMap() {
                      var Esri_WorldImagery = L.tileLayer(
                     "http://server.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer/tile/{z}/{y}/{x}",
                     {
                   attribution:
                   "SYROCO 2024" +
                     "NIMRD 'Grigore Antipa'"
                    }
                   );

              var Esri_DarkGreyCanvas = L.tileLayer(
             "http://{s}.sm.mapstack.stamen.com/" +
             "(toner-lite,$fff[difference],$fff[@23],$fff[hsl-saturation@20])/" +
             "{z}/{x}/{y}.png",
            {
            attribution:
            "SYROCO 2024" +
            "NIMRD 'Grigore Antipa'"
             }
             );

            var baseLayers = {
             Satellite: Esri_WorldImagery,
            "Grey Canvas": Esri_DarkGreyCanvas
            };

          var map = L.map("map", {
         layers: [Esri_WorldImagery]
          });

         var layerControl = L.control.layers(baseLayers);
         layerControl.addTo(map);
         map.setView([43, 35], 7);

        return {
        map: map,
         layerControl: layerControl
         };
         }

        // demo map
        var mapStuff = initDemoMap();
        var map = mapStuff.map;
        var layerControl = mapStuff.layerControl;

         

                         $.getJSON("water-gbr.json", function(data) {
                          var velocityLayer = L.velocityLayer({
                         displayValues: true,
                         displayOptions: {
                         velocityType: "GBR Water",
                          position: "bottomleft",
                         emptyString: "No water data"
                            },
                         data: data,
                          maxVelocity: 0.6,
                         velocityScale: 0.1 // arbitrary default 0.005
                        });

                      layerControl.addOverlay(velocityLayer, "Ocean Current - Great Barrier Reef");
                       });

                        $.getJSON("currents_6Dec2024.json", function(data) {
                       var velocityLayer = L.velocityLayer({
                        displayValues: true,
                        displayOptions: {
                        velocityType: "GBR Water",
                        position: "bottomleft",
                        emptyString: "No water data"
                        },
                          data: data,
                         minVelocity: -0.5,
                         maxVelocity: 0.3,
                         velocityScale: 0.1 // arbitrary default 0.005
                       });

                         layerControl.addOverlay(velocityLayer, "Black Sea Current - Romania");
                           });`