The spiky bromeliads are ok. Your frogs will do fine with them. Make sure that you treat your plants before placing them in the tank, you don't want to introduce any nasties in your new build. I soak mines in the sink with dishwashing liquid and about two capfuls of bleach for about 30 mind and then rinse them very thourougly.

My wife loves when I boil leaves, she likes the way it makes the house smell!