I went to a local plastic manufacturer and ask for a 3 foot long tube × 6 inches to be cut for me, the body is 28" and the collection cup is 6". The neck that connects the two is 7" tall x 3" wide.
In addition they cut two 6" circles with a 3" hole for the tube to connect the top and bottom. The last two things were a 6" lid
and a base 8x8".
I cut the holes for the intake and return with a hole saw and epoxied the fittings.
I purchased the venturi valve for $15 online. I glued everything with acrylic solvent, very easy to do.
This ran my 135 gallon for 8 years and is still serviceable.
I hope this helps. I saved a ton of money and so can you. You can modify to suit your needs.
I hope this helped!!!