Is this the proper way to remove a unit group for leaks?

[Rugarus]

• Update Income Tier1 Goldmine
  • Events
    • Time - Every 0.10 seconds of game time
  • Conditions
  • Actions
    • If (All Conditions are True) then do (Then Actions) else do (Else Actions)
      • If - Conditions
        • Integer_Seconds Equal to 60
        • TempBool Equal to False
      • Then - Actions
        • Unit Group - Pick every unit in (Units in Level Slayers <gen>) and do (Hero - Set (Picked unit) Hero-level to ((Hero level of (Picked unit)) + 1), Show level-up graphics)
        • Unit Group - Remove all units of (Last created unit group) from (Last created unit group)
        • Set tempSlayerGroup = (Last created unit group)
        • Set TempBool = True
        • For each (Integer A) from 1 to (Number of players), do (Actions)
          • Loop - Actions
            • Player - Set (Player((Integer A))) Current gold to (((Player((Integer A))) Current gold) + Goldmines[(Player number of (Player((Integer A))))])
            • Player - Set (Player((Integer A))) Current gold to (((Player((Integer A))) Current gold) + Goldmines[(Player number of (Player((Integer A))))])
        • Wait 5.00 seconds
        • Set TempBool = False
      • Else - Actions

 

[apsyll]

There are two ways to remove the unit group
Dynamic Unit Groups

This trigger will instantly destroy dynamically generated unit groups.

Unit Groups

• 
  Trigger
  • 
    
    Events
    • 
      
      
      Event
  • 
    
    Conditions
    • 
      
      
      Conditions
  • 
    
    Actions
    • 
      
      
      Custom script: set bj_wantDestroyGroup = true
    • 
      
      
      Unit Group - Pick every unit in (Playable Map Area) and do (Unit - Hide (Picked unit))

Another way to avoid a group leak is to store the group into a variable, and then destroy it manually.

Unit Groups

• 
  Set GroupVar = Pick every unit in (Playable Map Area)
• 
  Unit Group - Pick every unit in GroupVar and do (Unit - Hide (Picked unit))
• 
  Custom script: call DestroyGroup(udg_GroupVar)

This is useful if you want to use the group more than once in the trigger.
I always use the post from Ralle here: Things That Leak
That is a good source to learn about the leaks and get the right native before you know them out of the top of you head

You should also use a own variable iinsted of IntegerA because this could cause problems.
also wait is evil maybe start a second timer that sets the boolean to false.

 

[Rugarus]

Regarding the first trigger, are you not removing the unit group before it's even created?

And what is the 'bj' supposed to mean?

 

[apsyll]

Bj is a blizzard made prefix for some of their natives, I'm not that sure about the differences if you want to learn more about this look in the tutorial section.

It doesn't remove the group by call it set the flag that the next group will be removed if not needed anymore.
So you have to set it every time you dynamically create a group like by pick all units in region and do...