I checked in a thread on our New Jersey Aquatic Gardeners Club forum and found these places listed in Morris County.
http://www.njagc.net
Welco-CGI
http://www.gts-welco.com/gts-welco.a...=214&ptid=5#nj
Pine Brook
289 Change Bridge Rd.
Pine Brook, NJ 07058
973 575-1612
Hours: 7:30 - 4:30 M-F
Welco-CGI
259 Route 46
Dover, NJ 07801
973 366-5501
Hours: 7:30 - 4:30 M-F
Fire Fighters Equipment Co.
3053 Route 10 East
Denville NJ 07834
973 366-4466