Once both of them are adults, a pair could live in a 55 gallon safely, even though it's a bit on the small side. If you did have the space, I'd suggest a 65-70 when they're fully grown, but for now house them in something that they still have enough space in. Here's some care-sheets if you haven't found them already: http://www.reptilesmagazine.com/Natu...do-River-Toad/ http://www.frogforum.net/content.php...n-and-Breeding And also, do you supply them UVB?