The best replacement for reactor is jetboil.

The best alternatives to reactor are rated as following:
★★★★★  jetboil
★★★  luminox
★★★  kalkwasser
★★★  inductor
★★★  diffuser
★★  proactor
★★  orbital strike
★★  skimmer
★★  responder
★★  regenerative bio steel
★★  don davis
★★  dosing
★  calcium reactor
★  dosing pump
★  biosteel
★  transformer
★  automated refinery
★  canister filter
★  pressurized water reactor
★  isolation transformer
★  refugium
  kalk reactor
  boiling water reactor
  cstr
  heavy water reactor
  balling
  2 part
  fission reactor
  continuous reactor
  nuclear bomb
  two part
  load reactor
  harmonic filter
  nuclear reactor
  cyclotron
  balling lite
  choke
  phosban
  plug flow reactor

Your alternative for reactor is not listed? Suggest!
Speaking about reactor, one probably shouldn't forget about capacitor bank.

Other search terms related to reactor and their ratings are:
★★★★★ capacitor bank
★★★★ ph controller
★ biopellets
You have in mind a companion for reactor and it is not yet here? Propose!



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reactor
jetboil
luminox