my Growling Grass Frogs (sounds more posh than Southern Bell Frogs) love the water. during the day they sunbath on plants and wood. they are used to it me approaching the enclosure from inside and stay where they are but when I walk by outside the windows they all jump and hide IN THE WATER (that's what they do in the wild as well) and during night time they all rest more or less in the water or on the ground at the edge of the water.
mine do use the water every now and then to have a soak or a #2 despite I water them with a weed killer pump as well once or twice a day to keep the enclosure moist. (I only have a small, flat bowl with water in the enclosure for easy water change)
I feed my frogs with all sorts of insects and moths I catch in the wild. flies from a fly trap. small worms out of the garden (funny to watch the little brown ones fighting for one worm each frog on one end of the worm (spaghetti-kiss ). isopods, beetles, mayflies, stoneflies, damselflies (the red and blue small dragonfly look-a-likes) and last but not least crickets (note to myself - must order a new lot). the Growling Grass Frogs will get freshly morphed brown frogs when they are ready (not cruel, that's what they do in the wild as well) I don't feed them meal worms (they are too fat with barely any nutrition and can make the frogs constipated).
don't feed your frogs only flies and meal worms, they may even start to breed if fed properly.