Don't add "DAWN" or PALMOLIVE" to the black tank------why you Say ??

[Tapper]

Excellent info ForBruce, thanks for taking the time to post.

[315RLTSinPA]

I don't use anything and no problems with the sensors

[huntr70]

I've found that "Green Gobbler" drop in's from Amazon work great.

Best thing I have found in 20+ years of RV'ing.

They have several products, so make sure you get the RV treatment.

[Rick B]

let me first say that for 30 years i was a professional in the commercial detergent manufacturing industry. So my reasons are based on fact not here say.

A low alkaline soap like Dawn or Palmolive (safe on hands) will generate suds when mixed with water. By adding 3-5 gallons of water and this soap to the black tank and driving you will generate a HIGH suds level in the tank .

Suds is made up of water and soap and as the mix takes place the expanded suds will rise above the remaining level of water. The problem is suds offers no "SPLASH" or scrubbing action to clean sensors or break down poop and paper.

Ideally adding an HE-detergent like what is used in a "Front loading " washing machine offers 2 features. It produces a LOW suds level and has "Surfactants" (makes water penetrate) and has a higher ALKALINITY (not good for hands) then pot soap which break down the greasy stool better along with paper.

This way as you drive you get more splash and scrubbing action in the tank.

So, make a mixture of "BORAX" and "Tide He-Laundry Detergent " ( or any He-detergent) . The borax will soften the water, release oxygen and increase the alkalinity (ph9 ) to help bacteria break down the nasties.
(even if your water is considered soft--soil loads have the effect of increasing hardness in the water )

the photos below show examples.

Thank you for this factual information. Do you know if the HE pods contain the softener, surfactants, and higher alkalinity? No mixing powder required ...

[LanerC]

Can you recommend a quantity of each to use when ‘dosing’ a black tank?

I use 1 cap-full of he laundry soap with 2 oz of tst to start with then add another cap full in 3 or so days if hot out. works good!

[CVN Cheng]

I'll never understand the fascination with "cleaning" a tank you're just going to poop in tomorrow.
I've considered going to see-level indicators but we tend to go about 12-14 days before running low on fresh water and have never overflowed a black or gray tank so it's kind of a non-issue for us.
Even when we had a smaller rig (with smaller tanks) we never got to the point of being in trouble with waste water volume.

But having spent 35 years in Engineering on Navy ships, I'm more than familiar with waste management and suds are not your friend. If you're going to add soap, definitely a non-sudsing flavor would be best in my professional opinion.

Use whatever works best for you and flush with flair!

[ronb94]

5 lb bag of ice helps the mix too

[Ski Pro 3]

I use 2 pods of dishwashing detergent. My brand of choice is Cascade Platinum. I also add 2 to the grey water tank. Both do a wonderful job keeping 'things' in suspension and breaking them down, including the paperwork, to slurry. No 'lumps' if you get my meaning. Plus it makes the toilet smell good.

[Dick Noble]

We use dishwasher detergent also. We also add a bit of Calgone to soften the water. We do this before we drive. Soft water seems to penetrate better and has less minerals. We still have problems with the sensors, but I am working on that..

[stroguy]

We have 180 mile trip tomorrow. We are going to try the HE detergent and Borax. Our grey has fidgety for quite some time.