Suitable for small to medium ponds, the Pondmaster 1000 Filter is recommended for ponds up to 1000 gallons in size. Easy to use, simply connect to a submersible 500 GPH water pump. Because of this filters low profile, you can submerse it in water as shallow as 6". Water passes through 2 types of filtration, chemical-a fine carbon pad and biological-a coarse filter pad. Comes complete with 3/4" ID tubing and fittings. Will not eliminate blanketweed / string algae.