Is anyone else seeing this as bizarre?
I mean, 1.25 seems fairly common. So, you could have a manufacturer (like friggin' Reef Octopus who makes the danged 1.25-inch return pumps) have a simple 1.25-inch return jet.
OR, you could have, "I run a 1.25-inch silicon tubing into a 1.25-inch pipe, up to the top of my tank, where I then have more plumbing parts than for the rest of my tank. I have the 1.25-inch split with a 1-inch T, then from each end of the 1-inch T it then splits into two 3/4-inch T's (4 total), which each have a 3/4-inch outlet into my tank. Unfortunately, that means that my screen top project required 328 right angles for all of the various openings, and unfortunately my tank is shaded by all of the pipes running into the backside of my tank, but the FLOW!"
I really don't want the Flying Spaghetti Monster of pipes to allow me to effectively use a simple 1.25-inch pipe from my return.
Are you feeding anything else outside the return? do you have reactors/uv/anything else being fed from the pump or is it pump straight to the tank?