Valterra Odorlos V77002 Holding Tank Treatment (40oz Self Measuring Bottle),1 Pack

Really impressed with the quickness that this removed smells from our black tank. We camp every month or two and leave about 5 gallons of water in our tanks. Last treatment we tired really didn't hold up in summer months and left a big stink after sitting for 6 weeks. After flushing our tanks repeatedly and using this our tank smell went away in about 24hrs. Pretty impressive. After being parked for a month we are getting no smells in the camper. Good stuff.

This product is easy to measure and stops the stink out of the black tank. It seems to work better than the blue packet products.

It eliminates all smells in between dumps! Amazing!

We use Odorlos V77002 exclusively. After draining the Black Tank, then Gray Water Tank, simply pour this into you toilet with a little water, then flush. Within a few minutes that stink goes away and it begins to break down bacteria in your tank. Works great.

This works the best out of the few liquid ones we’ve tried. It’s a little more but it works better.

This stuff is amazing. It has almost no odor out of the bottle, but the black tank did not smell at all after having it in it for over a week (with both number 1 and number 2). I will definitely buy it again.

The black tank in an RV can have two stages. One is to break down the material. The second is the terrible odor stage. I believe the second stage is caused by available oxygen (not sure about this) Anyhow the second stage really stinks. This product somehow stops the second stage not allowing bad odor. I have used it for two years with; no odor problems.

This stuff is excellent and easy to use. The bottle makes measuring a no brainer and prevents spills. It doesn't burn your eyes or smell so much like chemicals you can't breathe. I use in 35 gallon holding tank and just add a serving 1/week and nothing ever smells!