Standard: WRC BUL 165 ... and are limited in use to -90F for the 2-1/4% Ni grade (ASTM A203 Grade A) and -150F for the 3-1/2% Ni grade (ASTM A203 Grade D).
... Read more
By Carl Strohmeyer & Steven Wright Updated 1/2/18. Aquarium Filter Media; Types (Carbon, etc.), Capacities, Replacement/Care and more (This applies to ponds as well).
... Read more