A Collector Box is included in the two largest pond systems.
The Collector Box serves as a junction box and a pre-filter. It allows for up to four - 4 inch drain or skimmer pipes to be connected to the pond side while the opposite end has two - 3 inch outlets for connecting multiple pumps. Each of the 4 inch return line openings has a slide valve built in, to adjust water flow. The box comes with a large removable net for filtering out debris.
The Advantage Collector Box is available in two sizes:
Small comes with 3 four inch inlets - Dimensions L-33" W-28" H-25"
Large comes with 4 four inch inlets - Dimensions L-38" W-32" H-27"
For more exact dimensions, look at the following two pictures: (picture 1) (picture2)
An auto-fill can help avoid a potential disaster when re-filling your pond. It makes maintaining a pond much easier and with an auto-fill you do not run the risk of forgetting to turn off the water. An auto-fill will automatically keep the pond water at the same level all the time. It is important to note that cheap auto-fills can pose a great threat. Buy a quality auto-fill, not a plastic one.