Crystals in plastic containers

[vikingHB]

I've noticed that sugar crystals have formed in the thin clear plastic syrup containers, but not in the thicker plastic (maple scene jugs), or glass containers.
In the same batch I did use glass, thicker plastic, and the thin plastic. Therefore it is not due to longer evaporation on a batch. Has this ever happened to anyone else, or does anyone have a clue why this may have happened? Next year I'm staying away from the thin clear plastic.

[highroadsyrup]

I have had this happen in glass & plastic before. I checked one time and my brix was too high in the plastic container, the other time was in the glass containers, brix was ok so I laid it to the bottles touching each other after jugging. I just started using some of the clear plastic containers this year, we call the ketchup bottles...no problems so far.