seal it back up and try and keep it in a dry place, as if it gets damp or wet, i think it can go off
if you can afford it and you are using di only, get an other di vessel and when filling up the tank attach this someone where along the line as this will help to filter the water going in to the tank and can be used to reduce the tds of the water in the tank and will also help you getting max use out of your resin, and u wil be suprised how long the resin willl last then, i do this woth my old resin and can reduce my water from 90 - 30 tds whilst it is filling up all with resin that would other wise go in the bin