Walex Porta-Pak RV Toilet Treatment Drop-Ins, Treats Black Holding Tanks, 10-Pack, Fresh

from Blossom

These are the best thing going for your RV black and grey water holding tanks. They cut down the odor like you can't imagine. I got the tip from a fellow RV person who lives in their's full time like we do. And, we will only use these from now on. If you give these a try, you will find that it wo...

from PDG25

Great product. We have used the other brands but this one seems to work the best in our RV especially when it's over 90 degrees out.

from cindy

I love theses tabs! they were quickly and they work great! they break down the waist and the TP and the smell is gone so quickly. I've used other products that cost more and promised more but they didn't come even close to doing that! this is what I will use from now on!

from Desi

I will continue to purchase this. satisfied - keeps trailer smelling fresh.

from CeeBee

These work better at keeping the blank tank doors down than the other brands were tried. We'll try something else but always end up back with this brand.