A few months back I bought a bottle of your Cactus Juice. I was careful to follow the directions as it was my first time using it and I didn't want to mess things up. I used some of the resin to stabilize a few rounds of pen blanks and it worked great as intended. Once I was done, I was told not to pour the used resin in with the unused resin, but to pour it in a mason jar and seal it up for next time. I did so and stored it in my house so it was temperature controlled. A few weeks later I went

I am sorry you had problems with storage of Cactus Juice.  I am not sure who told you to pour it into a mason jar and seal it up but they were dead wrong!  Cactus Juice does not evaporate and does not need to be sealed up.  Actually, sealing it in a glass jar is a sure fire way to experience exactly what you have experienced.  It is complicated why it happens but it sure will just about every time regardless of the temperature.  Pouring into a plastic container, even with a sealed lid is fine since plastic will allow some air to get thorough.  This is covered in my directions on using Cactus Juice here:  https://www.turntex.com/product/cactus-juice/cactus-juice-resin-and-dyes#directions  In the future, please disregard the information you read on other sites or see on youtube.  There is a LOT of bad information out there!