The best replacement for ich is velvet.

The best alternatives to ich are rated as following:
★★★★★  velvet
★★★★  fungus
★★★  ick
★★  fda
★★  sand
★★  white spot disease
★★  mir
★  brooklynella
★  sah
★  flukes
★  ish
★  white spot
★  fin rot
★  velvet disease
★  marine velvet
★  bubbles
★  columnaris
★  ichthyophthirius
  amyloodinium
  athene
  fungus fish
  hirn

Your alternative for ich is not listed? Suggest!
Speaking about ich, one probably shouldn't forget about fish.

Other search terms related to ich and their ratings are:
★★★★★ fish
★ quarantine
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Google Trends

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ich
velvet
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