Re: what do you use to hold your shisha?
I don't recommend ziploc bags because they can absorb liquids over time as can any other container made of low density polyethylene (resin ID #4, the number inside the recycle triangle). Try to find one made of polypropylene (#5). Polyethylene is fine for lids (#1 is common for lids).
Try some of the Ziploc polypropylene containers like Dee mentioned. I personally recommend Rubbermaid TakeAlongs as they are cheap and a 10 pack of the square 2.9 cup ones can be found for $3-4 at Walmart. They are sized well to hold 250g of tobacco. If you want to go more expensive, try glass containers.
In case you are wondering, here are some other common resin ID numbers you will come across. Try to avoid PVC (#3) for foods and liquids:
1 - Polyethylene Terephthalate (PETE)
2 - High Density Polyethylene (HDPE)
3 - Polyvinyl Chloride (PVC)
4 - Low Density Polyethylene (LDPE)
5 - Polypropylene (PP)