My sea moss should last a year. Each person's needs are different for dosage, but a couple spoonfuls a day should be fine. Cara and I put a big handful in our smoothies daily. Sea Moss grows in the north Atlantic and very southern part of the south Pacific, where the ocean is very clean and yes it has been tested for heavy metals which you shouldn’t concern yourself with anyway because all seaweeds have Algin which binds heavy metals and carry them through and out of your body. You’ll never get heavy metals from seaweed, even if it was growing in radioactive waste (which my sea moss isn't anyway). Yes it’s simply sun dried and bagged. There is still ocean debris tangled in it and it smells really strong when you first open it, which is why it needs to be washed several times really well. It sells out really fast so every batch is less than a month old. It expands to 4 times its size when wet, so even if you used it daily, it should last a month, unless you use it in a lot of recipes like Cara and I do. It's normal for the sea moss' color to range from white to black, and you may find white powder on it. That's sea minerals, and is nothing to be concerned about. In case you're wondering, the sea moss the type of collagen that builds up the ligaments and cartilage between your joints.