Considering I grew up in the same county, have you ever thought about hiking up in the Ramapo Mountains? - Ringwood has some really nice rocks that you can find up on and off the trails... There are some areas where the rivers\streams go over the rocks and you can get what you are looking for.
However they do have those lichen (spelling/green type of things growing on the rocks) - so you will need to scrub it off with a steel brush or something like that) and treat it. (Make sure you do all your checks to make sure it doesn't change your PH)
If you go along rivers, they will be round and polished almost. Streams are always fun, but I prefer trails (rocks seems to be a little more what you are looking for)
Thanks ! Yeah I live in Clifton, so that's not far for me. The ADA rocks have grooves, and a rough texture like Seiryu stone or Ryuoh stone http:// www.thegreenmachineonline.co...eiryu-stone-kg
I did some research and most of these are a type of limestone or sandstone, which do affect water chemistry, but correct me if I'm wrong shouldn't be an issue if you change your water once a week like you should in our hobby ?
Thanks for listening