depending on the reverb there may be a wet/dry mix or reverb amout or somethign that lets you adjust the actual amount of reverb being applied to the sent signal in the plug in itself. usually i send it maxed out depending on what im doing, and then adjust the the wet/dry mix or volume fo the aux send to where i want it to be.
Some things i dont understand i where are you sending the aux channel (reverb) is it going to the main mix or are you sending somewhere else?
It sounds like you are sending multiple tracks to the same reverb? Which is fine its just unlear what the percentage amount is.
One way to do this is say for your snare. Your snare track is beind sent to a drum group buss, the aux is sent to lets say snare fx 1, i think i usually have the send amount to 0.00. insert the reverb into the aux channel and adjust the reverb for the sound you want. From this point you can either send the aux channel to the drum buss along with the snare or your stereo mix or wherever. If its too loud adjust the wet/ dry or reverb amount at the plug in or simply pull the fader down at the aux channel until you are satisfied with the result. If you have too much reverb maybe your snare trackisnt being sent to the right place.
The other possibility is on the snare track where you route the snare aux channels if you select a button to the right of the level and turn it orange it think it sends pre fader so it works a little differently. make sure that the button there isnt orange that could be the culprit.