There is another trick if flow is too high. But a bit hard to explain.
First, you need to make an small movable sleeve around your standpipe.
Get a PVC coupler, cut it in half lengthwise, so it slides over a pipe.
Then, take a chunk out vertically, so you can clip it onto a pipe.
(It should look like a "C" if viewed from top)
Second, drill a pretty big hole at the very bottom of the standpipe. About 1/4 diameter of pipe.
Then, you take the clip you made, and cover the hole.
Re-install everything and get it running as normal.
Then adjust the clip up and down to cover the hole.
Since that hole is deep, there is more pressure, so a lot more flow.
Now it is a bit strange, but there are two modes:
1) Just a bit of flow through the hole.
This "assists" the durso, increasing total flow.
2) Almost all the flow through the hole.
Essentially replacing the durso.
I run this way, and ended up simply removing the top part.
In between those modes, it makes a ton of noise.
When 100% of the water is through the hole, it makes a ton of noise.