I am using a Dowex 1x4 chloride form resin to do an ion-exchange.

I am following a protocol where the ion exchange is performed in a beaker under stirring.

First of all I wash the resin with water, then I condition it with 5%HCl and finally I wash it with methanol.

I dissolve my sample in methanol and then I add the resin and leave to stir overnight. 

Once I filtered and rinsed the resin with methanol to recover my product I wash again the resin, recondition it with HCl and store it under methanol.

After using the resin four times it deteriorated, I see a sand at the bottom of the beaker.

Is it normal?

Is there any better way to store the resin?