IF you have a wide mouth bottle(s) of any type, then you should think about getting some of these. Makes them MUCH easier to drink out of.

  (You need to Login or Register

If you go to the fold-able plastic bottle, sooner or later you’ll get a pin-hole leak.

I have a stick of that glue you fix holes in fishing waders, the kind you melt the top with lighter and dab on the hole.  That works great on seam areas.

On flat areas I have a roll of that black waterproof tape you can buy at the auto parts store that seals coolant leaks in radiator hoses. Between the two you can fix many things besides just a leaky water bottle.