diff --git a/Buffer/BufferTick.h b/Buffer/BufferTick.h
index 8e6ac9093..70965dcfe 100644
--- a/Buffer/BufferTick.h
+++ b/Buffer/BufferTick.h
@@ -56,6 +56,22 @@ class BufferTick : public BufferStruct<TickAB<TV>> {
     Init();
   }
 
+  /* Grouping methods */
+
+  /**
+   * Group ticks by seconds.
+   */
+  DictStruct<uint, DictStruct<uint, TickAB<TV>>> GroupBySecs(uint _spc) {
+    // DictStruct<uint, DictStruct<TickAB<TV>>> _result;
+    // @todo: for each iter
+    // for (DictStructIterator<uint, DictStruct<TickAB<TV>>> iter(Begin()); iter.IsValid(); ++iter) {
+    // Load timestamp from key, TickAB from value
+    // foreach some timestamp mod % _spc - calculate shift
+    // _result.Push(_shift, TickAB<TV>)
+    // Convert to OHLC in upper method
+    return NULL;
+  }
+
   /* Callback methods */
 
   /**
diff --git a/Chart.struct.tf.h b/Chart.struct.tf.h
index 49c7c88f3..7074f67e8 100644
--- a/Chart.struct.tf.h
+++ b/Chart.struct.tf.h
@@ -32,6 +32,7 @@
 
 // Includes.
 #include "Chart.enum.h"
+#include "Serializer.mqh"
 
 /* Defines struct for chart timeframe. */
 struct ChartTf {
@@ -346,8 +347,6 @@ struct ChartTf {
   SerializerNodeType Serialize(Serializer& s);
 };
 
-#include "Serializer.mqh"
-
 /* Method to serialize ChartTf structure. */
 SerializerNodeType ChartTf::Serialize(Serializer& s) {
   s.PassEnum(THIS_REF, "tf", tf);
diff --git a/Indicator/IndicatorTf.h b/Indicator/IndicatorTf.h
index a64d22338..956fb2b45 100644
--- a/Indicator/IndicatorTf.h
+++ b/Indicator/IndicatorTf.h
@@ -30,6 +30,7 @@
 #endif
 
 // Includes.
+#include "../Chart.struct.tf.h"
 #include "IndicatorCandle.h"
 #include "IndicatorTf.struct.h"
 
@@ -51,14 +52,28 @@ class IndicatorTf : public IndicatorCandle<IndicatorTfParams, double> {
   /* Special methods */
 
   /**
-   * Class constructor.
+   * Class constructor with timeframe enum.
    */
-  IndicatorTf(ENUM_TIMEFRAMES _tf = PERIOD_CURRENT) { Init(); }
+  IndicatorTf(uint _spc) {
+    icparams.SetSecsPerCandle(_spc);
+    Init();
+  }
 
   /**
-   * Class constructor.
+   * Class constructor with timeframe enum.
    */
-  IndicatorTf(ENUM_TIMEFRAMES_INDEX _tfi = 0) { Init(); }
+  IndicatorTf(ENUM_TIMEFRAMES _tf = PERIOD_CURRENT) {
+    icparams.SetSecsPerCandle(ChartTf::TfToSeconds(_tf));
+    Init();
+  }
+
+  /**
+   * Class constructor with timeframe index.
+   */
+  IndicatorTf(ENUM_TIMEFRAMES_INDEX _tfi = 0) {
+    icparams.SetSecsPerCandle(ChartTf::TfToSeconds(ChartTf::IndexToTf(_tfi)));
+    Init();
+  }
 
   /**
    * Class constructor with parameters.
diff --git a/Indicator/IndicatorTf.struct.h b/Indicator/IndicatorTf.struct.h
index 8e82a67bd..5feae87e4 100644
--- a/Indicator/IndicatorTf.struct.h
+++ b/Indicator/IndicatorTf.struct.h
@@ -30,10 +30,18 @@
 #pragma once
 #endif
 
+// Includes.
+#include "../Indicator.struct.h"
+
 /* Structure for IndicatorTf class parameters. */
 struct IndicatorTfParams : IndicatorParams {
+  uint spc;  // Seconds per candle.
   // Struct constructor.
-  IndicatorTfParams() {}
+  IndicatorTfParams(uint _spc = 60) : spc(_spc) {}
+  // Getters.
+  uint GetSecsPerCandle() { return spc; }
+  // Setters.
+  void SetSecsPerCandle(uint _spc) { spc = _spc; }
   // Copy constructor.
   IndicatorTfParams(const IndicatorTfParams &_params, ENUM_TIMEFRAMES _tf = PERIOD_CURRENT) {
     THIS_REF = _params;