How many days to fill gray and black holding tanks???

37 gallon gray and black tanks in our TT, and it's just DW & me. We use regular dishes and take daily Navy showers. The black tank will go at least a week, but we'll fill the gray tank (and empty the FW tank) in 2-3 days.
But - I have a 30 gallon drum in the back of the F150 and a 12V pump. Gray water gets pumped & taken to the dump station as needed.

We have 2 30 gallon grey tanks and a 30 gallon black, the black tank will usually last the 2 of us 5-6 days. The Galley tank will usually last at least that long as we eat on paper plates and only wash the dishes from food prep. The shower grey tank will last us 6 Navy showers, which might be 1 day if the DW is running around in the summer and "glowing" (sweating to most of us)... :D

Don't really pay any attention to the gages anymore, they are notoriously inaccurate and we've learned how to tell when the tanks a getting full by the sound

bowler1 wrote:
Based on your experience how many days can you go without needing to empty your holding tanks, and how reliable are your tanks guages? And of course how big are your tanks and how man people are camping with you?

I know this is relative but i am trying to get an idea.

I have 32 gallon black and gray. I am solo camping now and finishing today after 4 nights. I have used the shower sparingly. My guages show that i now have full black and gray tanks. Seems that would not be the case this quick with one person.

Thanks

Matt

Matt - you will get a wide variety of answers to this (largely because everyone's usage of the RV is different) and you may be able to get an idea of a rate for you from those repsonses.

My wife and I cook daily and exclusively use our bathroom facilities while camping, seldom using the campground toilet and never the bathrooms. We navy shower daily. We have 37 gallon GW and BW tanks. We eat breakfast, lunch and dinner in our RV. We don't use disposable plates or utensils so have to wash the dishes.

Black tank usage 5 days, maybe 6 days. Grey water 3 days.

As for the tank readings - BW tank sensors can get fouled easily (e.g. crud on the sensors including but not only toilet paper) and when they do they will read inaccurately. With usage of a BW tank flush the problem would be greatly reduced. Replacing the sensors with Horst Miracle Probes and flushing the tank after each use should cure the problem. In the grey tank the problem should not present itself with proper usage (reduce grease down the drains, for example).

The black tank sensors get dirty easily and are less accurate than the grey sensors in my experience. If you can see the black tank level looking into the toilet, that is the most accurate. My trailer has 2 each 32 gal. grey tanks and a 32 gal. black tank. The rear grey tank which receives the shower water fills the fastest when the wife & I are boondocking. We both are very conserving of water however we only have 32 gal. of freshwater so that is the limiting factor for us. The sensor electrodes are never at the top of the tank so you always have a bit more capacity when the full light is on; seems like a reasonable safety factor to me.