Add as much air to your pond as you can using air pumps and air stones to distribute the air (highly recommended for ponds that are heavily stocked). You can add the air directly to the pond, the filter, the waterfall and anywhere else you can think of.
ELL SOC.
These high-quality elbows are available in various sizes to suit the needs of your pond. Whether it's a small corner or a large corner, these bends will help you get the job done.
Reducing Brushing S x S
Reducers convert pipe to fit different sizes. These schedule 40 bushings reduce the internal sizes of a pipe to enable a slightly smaller pipe to fit the connection.