Do Ice Cubes in the RV Black Tank Really Work?

I did it once this year. We were getting ready to take a 4 hour trip. I filled 6 soda cans with water and put them in the home freezer a few days ealier.After adding some water to the tank, I guessed how much it would take to put about an inch in the bottom. Cut the cans off (carefully) the ice and drop the big can sized ice cubes down the toilet. They just fit through the opening. Did it help? I don't know I cant see in the tank as mine has an elbow right below the toilet. I'm sure it didn't hurt.