Drop-ins or liquid?

Here is the video. In my opinion it was not a very good test.

Find The Fit RV on YouTube. He did extensive testing of various black tank cleaning methods. As Dick_B said the ice cube method didn't fare well.

Dick_B wrote:
BTW the ice cube idea has been debunked. They just float round on the top.

If you do just about anything wrong it won’t work they way it’s supposed to.

The *proper* way is to have just enough water that the ice can move around freely on the bottom of the tank.

If you put so much water in that the ice is sloshing around above the deposits of course it’s not going to do anything.

What everyone else said. BTW, if you're doing things correctly, no reason I can think of to limit "#2". Biggest cause of problems I've seen is not using enough water when dumping or leaving the black tank valve open when hooked up to sewer and thus building your own magnificent poop pyramid in the bottom of your now dry black tank

As to tissue, we use Kirkland or Angel Soft because the wife likes those 2. Please don't waste money on RV tp. Just use what you normally use at home

Old-Biscuit wrote:

DoberGirl50 wrote:
Hi all! This weekend when draining the black tank, it was very slow. I've been wondering if the outer casing on the drop-ins isn't dissolving and clogging the drain pipes. I went ahead and bought the liquid form, but wanted to ask if any of you have experienced this and what you did to solve it. In case you're wondering, we limit the number of times we go #2 and only use toilet paper designed for RV/boat septic systems.

Slow to drain......
Check that the roof top tank vent line is clear.
Birds nest, debris even falling down so end of line is farther down into tank will cause slow draining issues

Vent line MUST be clear for tank to drain properly

Quick and easy check to see if vent is your issue
Trying draining tank...then Flush/hold toilet valve open and see if tank drains faster. Toilet open provides venting
If YES then tank vent line is obstructed/blocked
Run hose down vent line and blast it clear

If still drains slow with toilet open then tank dump valve may NOT be opening fully or you have a blockage at tank outlet.




As for chemicals......POO
Dihydrogen Monoxide is the ONLY chemical I use period for 40 years.
RV waste tanks are 'holding tanks' not processing units.
Fill dump repeat.
And if you smell it then you have a vapor barrier issue...find/fix that and no smells

Thank-You I agree

As for the Bath Room Tissue,,,most products are fine. Take a couple of squares (pieces) of it, put it in a glass, and shake. If it starts to break up then your fine. If it still holds together and looks like a wet Kleenex then you should not be using that one.

You want it to break up in your tank and not be a solid chunk.

wa8yxm wrote:


How fast it breaks down I do not know but I will say this.. I've seen several "obsess" on this to the point of doing tests. Scotts single ply was among the fastest to break down, Quilted Charmin the slowest.

We did a test 5+ years ago just for fun with 6 or so different brands including a couple specifically for RVs. What was interesting was one of the well known RV brands didn't disintegrate whatsoever and was like ordinary household stuff. IIRC it was Thetford. There's no regulations covering "for RV use" labeled TP so it's buyer beware. Somebody's making a killing off selling "RV" TP to unsuspecting RV-ers...

FWIW, the TP you want disintegrates into little pieces, none of it actually dissolves. I seem to recall it only taking an hour +/- to disintegrate. But I'm sure any ol' TP will work in most cases, esp. considering the size of some "logs" that gotta pass through the pipes & hoses.

Regarding TP.
A company called BOXED.com
It is a bit like Sam's Club in that they sell Sam's size packages (IE: 30 rolls of TP in one pack) the store brand is Prince and Spring.

That's what I"m using.. I have some others who use it as well. Good stuff.

How fast it breaks down I do not know but I will say this.. I've seen several "obsess" on this to the point of doing tests. Scotts single ply was among the fastest to break down, Quilted Charmin the slowest.

But by the time I take care of the paper work. (As you know no job is done till you finish the paper work) Flush. Pull up, and properly fasten. Get out side and pull the "T" handle. Even Charman will be broken up.

I use odor control chemicals every time. The black tank is open to the interior while flushing and open to the outside thru the roof at all times. When dumping, often there is only an open pipe to accept the hose and quite a stink can happen. Ask the "only use water" folks if they think a portable toilet would be pleasant if that blue stuff was not used. I don't consider doing something to reduce odor for everyone is a waste of money.

Treatment chemicals are a waste of money. Same for RV toilet paper. Just use lots of water when you dump.

DoberGirl50 wrote:
Hi all! This weekend when draining the black tank, it was very slow. I've been wondering if the outer casing on the drop-ins isn't dissolving and clogging the drain pipes. I went ahead and bought the liquid form, but wanted to ask if any of you have experienced this and what you did to solve it. In case you're wondering, we limit the number of times we go #2 and only use toilet paper designed for RV/boat septic systems.

Don't be stingy with the water when flushing. You should not have to limit the use of your RV toilet for #2. Have you used one of those wands to flush it out lately?