FYI - Sterilite brand and Food grade plastic

[CloruroDiSodio]

Sent a request to Sterilite regarding their plastic products to see if they would be saltwater safe. Looks good, here was their reply:
Thank you for contacting Sterilite. Our products are made of polypropylene plastic, which is a food safe material. The polypropylene used in our containers meets FDA requirements in the Code of Federal Regulations for all food contact excluding actual cooking applications. No Latex, BPAs, PVCs, Teflon, or other stain resistant chemicals in our manufacturing process.

 

[THE ROOK]

Plenty of people use the cheap gray containers for storing water. I did too until I realized my tds would creep up from 0 to 45 within about a week of storing water. Something in the plastic is causing that rise. I have since switched to Brute & the tds stays at 0.

 

[WaterKeeper]

Just dissolving gasses will cause the TDS to creep up on RO/DI. It may be some plastic leachate but my guess it is more like oxygen, nitrogen and carbon dioxide that cause the rise.