Food: When he is young you could feed smaller portions each day. Maybe one large cricket.
When he is about two inches and over you could start to feed him a bit bigger portions about every third day.
When he is a bit bigger than that, maybe 3-4 inches you could feed him bigger postions aswell.
There is no real amount of food to feed, especially when they are adult: If the frog is skinny feed more, if the frog seems fat, feed less (Note: These frogs are big/fat by nature so don't asume that the frog is overweight if he looks fat). I'm not sure how to tell that the frog is overweight though. I doubt it will even happen if you feed the right diet and a good amount.
My frog who is around 4 inches (these frogs are usually adult at 4-6 inches from what I know, though I've heard of smaller adults and abit bigger. Females are bigger than the males.)eats about six or seven big/medium crickets or earthworms every third to fourth day.
Types of food:
1. Pinkies are fatty and not so nurtious, so I would avoid feeding those.
2. Mice or fuzzies on the other hand am I uncertain of. There has been LOTS of discussions about wether to feed mice to frogs or not. If you would like to know more about this please check the thread "Controversy Over Mice" wich was posted a few months ago in this frog forum.
3. Fish I don't know about either. I know that some people feed fish to their frogs, I just donät know what kind of fish that are safe to feed.
4. Crickets are according to me a good staple diet. They should be gutloaded and dusted with calcium supplement.
5. Earthworms/Nightcrawlers can also be a good, but too much. I've learned latley that too much of these can cause problems with the frogs muscles.
6.Superworms/Mealworms are okay as an occasional food item. They are usually fattier than circkets and less nutritious. I've also heard stories of these hurting animals insides by biting them. I don't know if these are true, but if you want to be on the safe side you could pinch their heads of before feeding.
One more thing, they are also abit harder to digest than for example crickets from what I know.
7.Cockroaches I have had no experience with, but some feed them to their frogs. I think these should oly be fed ocationally since they I belive are also hard to digest.
Tempratures: Should be around 75 degrees farenheit.
Humidity: Some say around 80% humidity though I've heard that around 50-60% is the best.
I personally don't have a hygrometer in my tank I just water the substrate when it looks to dry.
One more thing about feeding, you should try to feed your frog with tonges since thse will reduce the risk of the frog eating the substrate and getting impacted.
It got kinda long, hope this helped 
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