I noticed you said you were planning to do a full clean-out once a week. As long as you spot clean and change the water every day, you only need to do a full clean-out of the tank about once every 3-4 weeks.

I'd remove the twiggy substrate and replace it with coco-fiber. Even if the twigs are small, they could injure the frog's throat or stomach if they are swallowed. They are pretty violent eaters, so if it can be swallowed it eventually will be.

lol, the good thing about pacs and quarantining is that they live alone. The only real quarantining necessary is to make sure you don't use the same tongs or equipment for another animal until the pac's 'quarantine' period is up.