Any know how to only send effects to the mains not the monitors?
Hi Rich, welcome to the forum.
How are you feeding your monitors? If you set up monitor mixes on buses and send them through the Aux outputs, you can just leave the FX Return faders down for the monitor mixes.
If you want help setting up the monitor mixes, attach your scene file to your post (see Choose File button below).
Sent my last scene, but i dont think I had any effects on at all
Well you have FX3 inserted into channels 1 & 2. That's an unusual way to use a time-based effect. Inserted effects are usually used to replace the original sound - e.g. DeEsser, EQ, Compression, etc. Time-based effects (Reverb, Echo, Chorus, etc) are usually used in Send/Return mode to they can be added to the original sound.
Because the effect is inserted into the channels, it will be present on the monitor mixes as well as the main mix. Change to using it in Send/Return mode and you can add it only to the main mix. I have attached your scene with this changed.