do you change its water late at night , as that can be a trigger , have you tried a smaller water container at night , but its probably attention seeking , has it only been happening since the arival of the ringneck....pete
The sound of running water (your showers) is probably triggering him to bath, maybe try running the shower in the morning for 30 secs or so just to see if you can get him to bathe in the morning....my rainbow will have a bath when he hears the washing machine draining (he lived in the laundry for a while).