Yes, you can. If you go to Moersch Photo Chemie you can find his tutorials under the given chemistry:
I think it's listed for the working soln' I do mine in small amounts. I think the shelf life is at least 6 months but it should be listed on his site.
Have fun. I just ordered another batch myself.
Yes, like Clive said make sure you tone outside. and don't dump the stuff in the sewage..!