its made out of pvc
. you take a 4" pipe as tall as you want to make it
and cap one end. near the end make a hole for 1" pvc
pipe. use elbow connectors to make the 1" pipe come up through the middle of the 4" to near the top and on the outside to about halfway. cut a hole near the top for an elbow connector. this is where the water will come out of the filter. it should be a good few inches down. the inner pipe should come up above this, or at least up to it. on the one outside, put an elbow and then a valve, you will need this to tweak the flow for perfect operation. now get a 2" pipe, this will go inside the 4". the 1" will be inside the 2". a 4" to 2" reducer will serve as a collection cup. i never found a 4 to 2 so i use a 3 to 2 reducer. this cup will go at the end of the 2" pipe sticking up. since the end cap is round you probably want to make some sort of feet. i used the 4" pipe and cut halves and glued them to the outside of my skimmer. put tube thingies on the end of the outlet and the valve, get a pump and hosing and attach it the pipe with the valve. an airline needs to go to the input end of the pump. this takes some tweaking with the speed of the water, placement and size of tubing.
if you can get it done, it will do amazing things for you and it is a lot less expensive.
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