Well worth reading
Says it all

http://www.frogforum.net/beginner-di...ivarium-2.html

My 2 cents:
I keep 10 dart frogs species.
At the moment I am caring for >40 froglets and numerous tadpoles; last count 48 ?
NO culling - ever. If I want them to rest ~~~ I separate them.
No....... breeders do not commonly cull eggs.
Personally , I have never had a conversation w/ an individual that breeds having admitted to this.
We all know what happens when you put 2 frogs of the opposite sex together
IMO, one should take the responsibility to be ready for it.

Nine years ago , when I started, the first thing I wanted to do was to put them together.
Nine years later, I have not done it. After a while we ALL gain the respect for all the reasons
this is frowned upon.

If you are planning to do this .......you will need a HUGE enclosure and lots of experience to mix species.
Experience ~~~ meaning having the experience with each particular species your planning to keep together.
Particular species~~~ meaning having logged hours of observing their behavior - housed alone.