diff --git a/advanced-reactor.html b/advanced-reactor.html
index a18e6a3..a1a7ea7 100644
--- a/advanced-reactor.html
+++ b/advanced-reactor.html
@@ -5,6 +5,7 @@
         defaults: {
             name: { value: "" },
             volume: { value: 0., required: true},
+            n_inlets: { value: 1, required: true},
             S_O_init: { value: 0., required: true },
             S_I_init: { value: 30., required: true },
             S_S_init: { value: 100., required: true },
@@ -31,6 +32,10 @@
                 type:"num",
                 types:["num"]
             });
+            $("#node-input-n_inlets").typedInput({
+                type:"num",
+                types:["num"]
+            });
             $(".concentrations").typedInput({
                 type:"num",
                 types:["num"]
@@ -41,6 +46,10 @@
             if (isNaN(volume) || volume <= 0) {
                 RED.notify("Fluid volume not set correctly", {type: "error"});
             }
+            let n_inlets = parseInt($("#node-input-n_inlets").typedInput("value"));
+            if (isNaN(n_inlets) || n_inlets < 1) {
+                RED.notify("Number of inlets not set correctly", {type: "error"});
+            }
         }
     });
 </script>
@@ -55,6 +64,10 @@
         <label for="node-input-volume"><i class="fa fa-tag"></i> Fluid volume [m3]</label>
         <input type="text" id="node-input-volume" placeholder="m3">
     </div>
+    <div class="form-row">
+        <label for="node-input-n_inlets"><i class="fa fa-tag"></i> Number of inlets</label>
+        <input type="text" id="node-input-n_inlets" placeholder="#">
+    </div>
     <h2> Dissolved components </h2>
     <div class="form-row">
         <label for="node-input-S_O_init"><i class="fa fa-tag"></i> Initial dissolved oxygen [g O2 m-3]</label>
diff --git a/advanced-reactor.js b/advanced-reactor.js
index 0a0bbcd..15369ec 100644
--- a/advanced-reactor.js
+++ b/advanced-reactor.js
@@ -8,7 +8,8 @@ module.exports = function(RED) {
         const Reactor = require('./dependencies/reactor_class');
 
         const reactor = new Reactor(
-            config.volume,
+            parseFloat(config.volume),
+            parseInt(config.n_inlets),
             [
                 parseFloat(config.S_O_init),
                 parseFloat(config.S_I_init),
@@ -29,13 +30,11 @@ module.exports = function(RED) {
         node.on('input', function(msg, send, done) {
             switch (msg.topic) {
                 case "clock":
-                    reactor.updateState(msg);
+                    reactor.updateState(msg.timestamp);
                     break;
-                case "Influent":
-                    reactor.setInflux = msg;
-                    break;
-                case "Effluent":
-                    reactor.setInflux = msg;
+                case "Fluent":
+                    reactor.setInfluent = msg;
+                    reactor.updateState(msg.timestamp);
                     break;
                 case "OTR":
                     reactor.setOTR = msg;
diff --git a/dependencies/reactor_class.js b/dependencies/reactor_class.js
index 29a3111..fd459d2 100644
--- a/dependencies/reactor_class.js
+++ b/dependencies/reactor_class.js
@@ -3,36 +3,37 @@ const math = require('mathjs')
 
 class Reactor_CSTR {
     
-    constructor(volume, initial_state) {
+    constructor(volume, n_inlets, initial_state) {
         this.state = initial_state;
         console.log(this.state);
         this.asm = new ASM3();
 
         this.Vl = volume; // fluid volume reactor [m3]
-        this.F = 0.0; // fluid debit [m3 d-1]
-        this.C_in = Array(13).fill(0.0); // composition influent
+        this.Fs = Array(n_inlets).fill(0.0); // fluid debits per inlet [m3 d-1]
+        this.Cs_in = Array.from(Array(n_inlets), () => new Array(13)).fill(0.0); // composition influent
         this.OTR = 0.0; // oxygen transfer rate [g O2 d-1]
 
         this.currentTime = Date.now(); // milliseconds since epoch [ms]
         this.timeStep = 1/(24*60*15) // time step [d]
     }
 
-    set setInflux(input) { // setter for C_in (WIP)
-        this.F = input.payload.F;
-        this.C_in = input.payload.C_in;
+    set setInfluent(input) { // setter for C_in (WIP)
+        let index_in = input.payload.inlet;
+        this.Fs[index_in] = input.payload.F;
+        this.Cs_in[index_in] = input.payload.C;
     }
 
     set setOTR(input) { // setter for OTR (WIP) [g O2 d-1]
         this.OTR = input.payload;
     }
 
-    get getEffluent() {
-        return {topic: "Effluent", payload: {F: this.F, C_in:this.state}};
+    get getEffluent() { // getter for Effluent, defaults to inlet 0
+        return {topic: "Fluent", payload: {inlet: 0, F: math.sum(this.Fs), C:this.state}, timestamp: this.currentTime};
     }
 
     // expect update with timestamp
-    updateState(input) {
-        let newTime = input.payload;
+    updateState(timestamp) {
+        let newTime = timestamp;
 
         const day2ms = 1000 * 60 * 60 * 24; 
 
@@ -50,8 +51,8 @@ class Reactor_CSTR {
 
     tick_fe(time_step) { // tick reactor state using forward Euler method
         const r = this.asm.compute_dC(this.state);
-        const dC_in = math.multiply(this.C_in, this.F/this.Vl);
-        const dC_out = math.multiply(this.state, this.F/this.Vl);
+        const dC_in = math.multiply(this.Cs_in, this.Fs/this.Vl)[0];
+        const dC_out = math.multiply(this.state, math.sum(this.Fs)/this.Vl);
         const T_O = Array(13).fill(0.0);
         T_O[0] = this.OTR;