You could get the drinking water system and just add the DI to it.
If you look under accessories you will find the DI add on.
Or you could just add the Drinking water system to the Oceanus too, this way you would have the lifetime waranty.
The drinking water kit is located under accessories as well.
We would put everything together for you ofcourse
Good luck and if you have any questions feel free to call the toll free number at the office and tell em Bryan sent ya and you want your 15% Reef Tank discount!
Bryan
1-866-260-REEF