Originally Posted by Absnova
Yeah I am leaving it empty. Using a powder pack. Was warned about build up.
this is what I would do if it was me but you will get many opinions on what to do.
I would be using a liqued instead of a powder for starters.
Odorlos or TST Orange Liqued form
I would look into installing some sort of a Tank washer like a Tornado to assist in cleaning the tank - the way I do it is when the Tornado is hooked up to the water and running I close the valve and let the tank fill with some water then re-open the tank - I also have a clear elbow or straight tube on the end of the hose so I can see exactly what is coming out of the tank - clean or dirty and keep opening and closing the valve until I do not see any more traces of toilet paper or poo.
If you have a way to clean it at home and use your house's main clean up hole you might be able to clean it good at home before your next trip.
you can also do the bag of ice trick - put a little water in the black tank and then dump a bag or two of ice and then drive it around for a bit to try and break up what ever is built up in the tank and then dump it out