5 Gallon Water bottles

I just had 6- 5gallon plastic Culligan water bottles given to me. Can I use those as fermenters even though it says "water only" on the bottom of the bottles? Also, has anyone had a bad experience brewing in those type of plastic bottles?

You should be fine to use them if they have a 1 inside the triangle on the bottom. I have heard that a 3 is still ok. A better bottle is basically the same thing (1 on bottom) and many people use those. Since a better bottle is 6.5 gallons and what you have is 5, you will probably want to scale down your batches to 4 or 4.5 gallons to avoid blowoffs.

Only issue I have heard is about lack of headroom during fermentation. You can reduce your recipe or split it into two of them , but that leaves a lot of room for O2 to cause issues too. The 6 and 6.5's are designed to allow enough headroom so blow offs are less likely to make a mess in your ferment room. A good plan since it is likely would be to install a blow off tube early and switch to an air lock after the active part of fermentation has subsided a bit. I am still learning, but have read a ton on this since I have access to a lot of theose 5 gallon bottles too.
Bob

I have some water bottles at work. They have a 7 inside the triangle. Would they be ok?

From everything I have read and heard, only the 1 and 3 are safe for brewing. Maybe someone who knows more can chime in, but from what I understand the other numbers let oxygen seep into the beer which is not good.

thanks guys, they have a number 7 on em. good to know now instead of later when i suffer from beer abuse