We use White Cloud 3 ply Ultra Soft and Thick, it's safe for septic tanks and RV's. I did the "dissolve test" using White Cloud, Charmin and Quilted Northern and the toilet paper sold specifically for RV's. I put 3 sheets of each in 1/2 cup of water and White Cloud fell apart the most, there was practically nothing left of it, I couldn't pick it up and squeeze it out. The other brands were just in a blob with a few stray pieces that fell apart. I could pick up the blob and ring it out. Now I'll have to get Scott's and do the test with it and the White Cloud. White Cloud is only sold at WalMart.