air lines as water tubing

Every so often I get on ebay and check the stuff and see if anyone is selling snakes. I know it is against ebay rules so I report them as I see em. I know I am a nerd, but it only takes a few secs. Moving on...while I was looking I saw someone selling 25 ft. of 3/16" air lines for an aquarium for only $2.50. Well the lines for my gravity watering are the same size so I went ahead and bought 2 rolls of it so I have plenty for future racks if needed. Anyone think there will be a problem with this? I got 50 ft. of tubing for $12 shipping. Even after shipping it still comes out cheaper per foot than anywhere else I can find online.