This fly fisherman has a howto on making a bug aquarium with plenty of pictures of creepy crawlies he has in his aquarium.
You’ll get a lot of activity when you first place the bugs in the aquarium but then things will settle down. The mayfly and stonefly nymphs will hide under the rocks or on the sticks. The cased caddis will roam all over the place. The sticks seem to be a popular place for the damselflies. The dragonflies will back themselves into the gravel and wait for their prey. The cranefly will burrow deep into the gravel. The hellgrammites will wander or burrow.