Thank you for your answer.
Yes my FPS are not very good, i’m not sure what is a “normal” value for them in the editor. When I load the StarterMap from StarterContent/Maps, my frames are at 55. Maybe my system is to weak, but on the other hand, when my game runs smooth on it, it should on much other also ^^
I was already thinking about your second solution, but at the moment I hav no idea how to handle that.
I thought I could add each spawned emitter location into an array and check before spawning if there is already this position in this array.
Problem with that is, that i would need a second array with the emitters is, checking if they are still valid to remove the from the emitter and location array.
But this array have to be run through every tick, so i’m sure this is not so good for the performance 
Is there an easier way to check if there is already an emitter on this field? (Because it’s all tile-based, the position of the emitters on the same field would be identical).
Another idea would be to change the graphics looks like toons, so i could change the explosions to solid materials, then it should, according to you, also be less frame dropping