x2 on the 'normal' toilet paper. Remember, an RV toilet is not the same as a boat's that has to pump sewage. As for chems, try without it. Modern RV sewage systems are tight enough that smell is usually no problem. Just remember with the toilet, water is your friend. Never leave the black water valve open, only open it when dumping and try to get everyone in the habit of filling the toilet bowl with water and making a 2nd flush after use to help prevent the dreaded "poop pyramid" in the tank just below the toilet. The extra slug of water helps distribute the solid waste in the tank so it will more easily drain out when the black valve is opened. Always dump black first and follow with grey to help flush out the sewer hose.