i don't have a grotto but those questions apply to any rat.
with only hanging out at the top, that's what rats do. they seem to like high places best. in any cage you will see your rats most often sleeping in the highest corner possible.
with the pee you won't be able to get them to stop peeing completely. they mark their space with their pee afterall. females will do this too.
with only hanging out at the top, that's what rats do. they seem to like high places best. in any cage you will see your rats most often sleeping in the highest corner possible.
with the pee you won't be able to get them to stop peeing completely. they mark their space with their pee afterall. females will do this too.