Submersible PRE-Filter/BIOFILTER RATED FOR PONDS UP TO 1000 GALLONS ALL MEDIA IS INCLUDED ! Easy to conceal under water. SUBMERSIBLE PRE FILTER >> NO CLOGGED PUMPS ! Water goes in thru the filter BEFORE the Pump ! Handles pump sizes from 250 to 1200 gallons per hour Dimensions : Dia. 15" Ht. 12" Mechanical and Biological Filtration for ponds up to 1,000 gallons. TETRA POND >> A NAME YOU CAN TRUST ! Activated carbon pad removes harmful chemicals, discoloration and improves water clarity. Excellent pump pre-filtration; increases pump life, reduces pump clogging and clarifies the water. Easy to maintain. Recommended Pump Dynamag 750 GPH by Tetra