local tiles = gettiles()
local water = {}
for _, tile in ipairs(tiles) do
   local id = tile.items[i].id
   if id == 622 then
      table.insert({tile.posx, tile.posy, tile.posz}, id)
   end
end

local pos = water[math.random(#water)]
useitemon('fishing rod', ground(pos))
wait(1000)