Dumpy's tend to be aggressive eaters. Keep an eye on them to be sure one isn't getting them all and leaving none for the others. A good way to tell if there getting overweight is the little ridges right over the round ear spots. If it starts to enlarge and flop over the ears, then there gettin too dumpy. X3 On the plus side, they are fun to tong feed, especially for kids. They attack the wiggly crickets, the kids get a show, and you know exactly which frog is getting what.

How big a tank do you have them in? 3 all together that must be a pretty big tank. And dont worry about them hiding. They do that. Take a look and see if there comin out at night. I never see mine in the daylight but the lights go out and out she comes. She knows the light going out usually means dinner time. XD And if they aren't quite yet its ok. They may take a bit to settle in. But Whites/Dumpys are very easy going and dont tend to be high stress frogs (though there are always exceptions). They aren't as susceptible to the oils in our skin like other frogs (either thicker skin or a slime coat or something that protects them. I'm not 100% sure) but handling can still be stressful. My Azy likes being handled, she settles into a calm position and can sit for several hours without incident. Other's have said there frogs hate being handled.

Its up to your frog if they want to be handled and its a good idea to wait till the tank needs cleaning. You can hold them and see how they act. If they settle in your hands and are relaxed then you can probably handle them without stressing them. If they wiggle to get away or are tense like they'll jump at any second its not a good idea to hold them.