It repeats 30 times, but this way it repeats 30 times in 1 tick.
I suppose you want to see 'those 30 repeats' happen, then you must give the system the chance to redraw. Redrawing the screen happens on the end of the tick.
To do this, you basecaly use the tick-loop. The events run top down (kinda). 1 top down = 1 tick. And it keeps 'ticking' as long as the game runs.
So you need a variable ... lets say 'counter' ... a number.
When you need to the repeat to happen, set it to 29. On the place where you now do the function call.
Now just ....
New event with condition ...
System compare 2 values ... 'counter' ... > ... zero
Substract 1 from 'counter'
All the other actions. from above.