Hmm, You have to distinguish between buss effects and insert effects. Usually reverb and delay effects are bus effects and dynamics and stuff like this are insert effects.
On the QU-24 you have on the right side of the faders four buttons named FX1 to FX4. With these buttons you can switch the channel fader mode from main fader to FX bus faders (this mechanism is called send on faders). That means that when you press one of these buttons you can use the channel faders to define the amount of the channel signal which will be sent to the effect. The Main fader will become the main fader of the FX send. The summarized signal of that FX send will be forwarded to the corresponding Effect slot and the result will be available on the FX return channels. Then you can adjust the effect level for the main mix by using these return channel faders. Don’t forget the to switch back to the main fader mode by pressing the LR button.
It would be helpfull when you read the manual carefully, especially the chapters 6.3 (hwo send on faders work), 10.8 Information of the FX setups and 10.9 (a step by step description how to add a reverb to channels, in fact more detailed as my expanation above and with images).
