Lots of fish eat em but especially gobies like the mandarin goby... they will live with you as long as your tank is healthy. You might have population "booms" and "dieoffs" but all in all they will never go away.
In fact copepods/amphipods are pretty important little guys. They are scavengers and also a great food source.
I see my perculas picking them off of rocks in my tank when they are hungry/bored.
(edited to add important note)
I forgot, if you decide to get a pod-eater like a mandarin (not that you need to do this anyway), you need to make absolutely sure that you have TONS of pods
and preferably a refugium that is generating lots of pods
otherwise they will not have enough pods
I will avoid getting a mandarin for specifically that reason until I get a big honkin fuge and I have millions of pods
waving signs that say "eat me"
A mandarin can eat a lot of pods
in one day.