xxBarneyxx
Fish Aficionado
If you are using a lot of it I would say rinse them off, put them in some slat water for a week and then do a water test to see if it has changed anything. If all the parameters are still good then I personally would say go for it. I dont see the point of putting lr with it in a seperate tank for a couple of weeks as it will take months to get any real life growing in it and if its your main form of filtration (ie you haven't got a load of LR with it)you would be better off doing a typical fishless cycle with it (using bottled ammonia).