The best replacement for crickets is grasshoppers.

The best alternatives to crickets are rated as following:
★★★★★  grasshoppers
★★★★  mealworms
★★★  locusts
★★  dubia roaches
★★  roaches
★★  cicadas
★★  superworms
★  cockroaches
★  frogs
★  mealworms leopard gecko
  tree frogs
  peepers
  wasps
  grasshopper
  hoppers
  silkworms
  mealies

Your alternative for crickets is not listed? Suggest!
Speaking about crickets, one probably shouldn't forget about buddy holly.

Other search terms related to crickets and their ratings are:
★★★★★ buddy holly
You have in mind a companion for crickets and it is not yet here? Propose!



Google Trends

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crickets
grasshoppers
mealworms