wow,
i am new to this forum but not new to aquatic pets. but after reading the posts on this site as a non-member for several months i am astounded that no one is giving out some very obvious information about these cool little frogs.
1) you cant just throw some water and fish/frogs in a tank and expect everything to work out. depending on the water in your area, just letting it sit may not be enough to make it tank ready - use some water conditioner.
2) you must have a fully cycled tank and have a good understanding of the nitrogen cycle (you are probably smelling ammonia). if you don't please return your frogs to the store and wait until your tank and your mind is ready to care for these animals.
3) these frogs don't eat daily (so don't feed them daily)
4) further they have terrible eye site and find food by smell or some other sensory method. thus it is a good idea to use an eyedropper/turkey baster to feed food right up close to the frogs. take a cup with some tank water, melt the blood worms in there, take some out with the eyedropper, squirt it gently in the direction of your frog
5) give these frogs lots of hiding spaces (SMALL flower pots, plants, etc)
6) now to address the concerns of filtration:
yes these frogs are found in shallow stagnant pools in the wild, yet i doubt they die every time it rains due to vibrations in the water. i used a very old and gummed up HOB filter (that had a prefilter to stop the frogs from getting caught in the intake) for the tank which used to hold my frogs the water trickled very slowly into the tank, i would recommend using either a very tiny sponge filter, a very crappy/gummed up HOB filter or be extremely diligent with water changes every couple of days.
finally)
these frogs are awesome and do cool little zen floats and poses around the tank. don't be alarmed if one isnt moving he is probably just meditating. also, they can go with fish and this might not be a bad idea as you seem to have difficulty doing clean up. maybe some dwarf corydoras or ghost shrimp would help keep any excess food out of your tank.
good luck with these frogs, if you get a healthy tank set up they will provide lots of entertainment for you and your son.