most will agree with heather, however i do keep a mixed tank. the potential for cross-contamination is very real. this could be parasites or other pathegens. w.c. animals all have a parasite load that can overcome the animals ability to keep them in check when exposed to new stressors such as being caught ,change in diet etc. deal with this by treating and quarantining the new arrival. another major issue to over-come is differing environmental conditions. if you feel confident that the environmental conditions are met for each frog within the enclosure. good. you chose a treefrog and a ground dwelling frog so they will utilize different areas of the enclosure. this is good. make sure no animals are predatory on each other. just because one animal is larger than the other doesn't mean that the larger one will eat the smaller. many times (not all) animals won't eat something that they don't recognize as a food item. this is more prevelant in wild caught animals. i suggest heavily planting so they can stay out of each others sight if they want. a water dish off the ground for treefrogs is nice. knowing your animals behaviors prior to putting them together will allow you to better see if there is a change. gd luck

i love the philippines and will be moving there permanently !