If you've got too many water beads on your hands then follow our tips to dispose of them in a responsible manner:
The most important thing you should NOT DO is put them down the drain. If you do this then the beads may be taken out into the environment (and possibly even out to sea) where they will be mistaken for food by wildlife.
The beads may also cause a blockage if you decide to flush them through your wastewater or sewer system. Just check out this poor guy who had Orbeez backing out of his toilet!
Instead, you've got a few options. You can store your water beads for use at a later date (some people advise adding a little salt to stave off mould, or storing in the fridge).
You can shrink your water beads back to (nearly) their original size. It is best to do this out of direct sunlight, as our testing has found that lengthy exposure to sunlight damages the internal polymer structure of the beads thus causing them to break apart. A warm, dry area should suffice. If you have a dehumidifier on hand then that would speed the process up.
If you're not interested in drying the water beads out then you can mix them into the soil in your garden. They will absorb and release water for 3 to 24 months before breaking down over a period of a year to years. Please note that the wide range in life expectancy in the soil is due to whether the beads are mixed deep into the soil (and out of sunlight) or whether they are still in sunlight (the beads will last a much shorter time if in direct sunlight).
Finally, if that doesn't suit you then it is best to put them into the trash. They'll end up in a landfill somewhere (which is a shame!) but due to the desiccating nature of landfills, the water beads will shrink down to almost nothing and only take up a few centimeters of space.
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Note: We originally recommended drying your water beads in sunlight as a means of speeding up the shrinking process. However, our experience has shown that lengthy exposure to sunlight can cause the beads to break down and therefore, we no longer recommend this.
Note 2: We originally described our water beads as being biodegradeable. However, we felt that this term was not accurate due to how long they take to degrade (a year to years).