they should do fine in either type of tub. i have an active culture for over a year within my pets tanks and they grow and breed fine with the same temps,humidity and light cycle. i have areas of rocks that cover leaf litter, bark, sweetgum balls, old moss, dead prey,feces, and fruit/veg scraps. if i lift these rocks both the speck like babies and adults can be found. some of my marbleds burrow near these rocks to get a meal but i also have crumpled leaves mixed within the substrate(coco fiber and cypress mulch) so the bugs will crawl around and feed and not just hide under rocks. you can find them outside in similar conditions under rocks, boards, logs, cinder blocks. if your able to kill a patch of your lawn and have some cardboard thats a good way to catch them too