local function on_tick()
  walk_on_tick()
  if game.tick % 60 == 0 then
    poll_on_second()
    walk_distance_on_second()
    if game.tick % 1200 == 0 then
      player_list_on_12_seconds()
    end
    if  game.tick % 180 == 0 then
      fish_market_on_180_ticks()
      if game.tick % 900 == 0 then
        refill_well()
      end
    end
  end
end

Event.register(defines.events.on_tick, on_tick)