Living and primarily camping in hot climates, I always add a bottle of the Thetford chemical along with a few gallons of water. Then I add more water. The GEO method works well, but I like the idea of pouring a strong chemical into my tank to help dissolve the toilet paper and the “other smelly stuff”.
If I need to dump and the tank isn’t full, I add water until it’s almost full, then dump. I then add more water and dump again. If you notice the common theme in these responses are ADD WATER!
It’s also a good idea about adding water prior to leaving home, then dumping when you get to the camp ground; shakes up the poo. Keep your ice in the cooler with your beer.
Between trips I add a bottle of chemical and add a few gallons of water.