If you keep to lakes or rivers, you don't need that same max depth as someone who's ocean fishing. (geekwrapped.com)
PADI Rebreather Diver is aimed at open water divers with 25 logged dives and nitrox certification, the course includes 5 dives with max depth 18m (twofishdivers.com)
These dives will not be at more than 12m depth (max depth for Junior Open Diver) and you will perform in the natural environment some of the skills you complete the previous day. (blueplanetdivers.net)