Black tank and toilet paper and chemicals

I've noticed that the label on the Costco brand of TP doesn't emphasize it breaks down quite like it used to. It now reads "septic safe" but that's about it. A few years ago Costco switched suppliers and I've wondered if the paper's ability to break down quicker changed also. It doesn't seem to break down as well for me as it did in the past.

I've also noticed that the old fashioned blue-stuff works a lot better than the green eco-friendly stuff.