i heard that zeolite is 'rechargable', does anyone know how its done?

It can be recharged by soaking it in saltwater, I think for about 24 hours, then rinsed with fresh water.

yep yep.. just make sure you're really careful about salting your tank if you've got zeolite in there!

Actually, I was suprised to be told that simply flushing it with a stronger salt solution for a mere 10 minutes was plenty to clear it of ammonia. Many of the breeders and dealers run large vats of fish kept clean with a circulation system that runs the water through a large reservoir of zeolite. This is swapped out and the used is flushed for 10 minutes in a salt solution - to be reused the next day.

thanks guys!
does anyone know how much the ppm should be?

I was told in a very offhand way that they used 1.0ppm..... but I am not sure whether that is actually what was in use or not.... it was a quick answer....... possibly given to concur with what I had already stated....

I usually use 1.0ppm and recharge for 20-30 minutes - simply because I am lazy and have no need of it sooner. Sometimes, since I keep multiple volumes of zeolite, I will dump a batch into the brine and forget it until the next day or so......