Bono’s crap?

Sheet of flexible rubber cut to shape – probably 3mil thick for endurance link

So you want to fill the toilet bowl to almost overflowing? Maybe a ziploc bag of water, half full so it can squish into the hole, filling all the curves and angles.

Kitty litter.
Kitty litter turns as hard as Krupp Steel

Put a water balloon inside the pipe and inflate it in place. That would seal it off tightly.
Also, if the plug breaks the rubber bits would just go down the drain.

Bleach is harmful to aquatic life, so I sort of hope you’ll use something less toxic. That said: a plunger would probably work for your purposes.

@ragingloli kitty litter will clog easily.

Use a roll of toilet paper.

I can’t help it – I just have to suggest…maybe use a toilet brush sprinkled with powdered cleanser or wear rubber gloves and use a sponge? What you’re suggesting sounds like an open invitation to a major problem at the most, and a bleach-water flood at the very least.

A soft foam ball, like a NERF ball, in a plastic bag stuffed in the hole.

I just noticed that you want to to be undoable. So do not use Kitty Litter, because you will have to hire a plumber to remove it.
I will second the balloon idea, in this case.

Can’t you just shut the water valve off while you deep clean the bowl?
You can overfill it with a water jug if you just want a soak.

….WHY do you want to do that?

Your question makes no sense because you say you’d like the toilet to be clogged and the clog to be “un-doable” but you also say you want to clean the toilet and presumably, continue to use it (otherwise why clean it?).

@KNOWITALL Get a five gallon bucket, fill it with water, pour the water into your toilet and see how full you can get your toilet bowl without it spilling over onto the floor.

@kritiper I turn the water off and pumice (we are high calcium here) and clean like a maniac. I don’t let chemicals sit in there for hours. Maybe you just need to clean it differently?

A less toxic cleaner is vinegar and blue Dawn heated up, mix in a little water and if your water is turned off, you can do the whole thing top to bottom. It can get a little fumes from the vinegar, but it works great. I know you didn’t want new ideas, but I can’t help myself when people want to use bleach.

Inside the tank just block the rubber plunger that stops the tank from filling or as others here stated turn off the water.

My late mother poured hot water into her toilet thinking that it would clean it better, but instead of cleaning, it blew up the entire toilet!
Plumber charged her over $200 to remove and then she had to purchase a new one at a huge expense.
For all that trouble, maybe purchase a new toilet .

@KNOWITALL That doesn’t answer the OP’s question. (Can I assume you haven’t tried to fill your toilet bowl like I previously mentioned??)

@Inspired_2write The OP is asking about the bowl, not the tank.

@capet There is a small vertical pipe in the tank that usually has a small plastic hose going to it. This hose fills the bowl after the toilet is flushed. Pour one or two cups of bleach down this pipe and let it sit for a while. The bleach will then be in the water passageway that is inside the rim. Otherwise, follow my earlier suggestion.

@kritiper It’s a toilet bowl dude, calm down. :)

There are plugs for bathtubs that are a circle of plastic that covers the whole drain area. Something like that but which is large and rigid enough to work in a toilet and NOT go down the drain would seem ideal to me. Typically they have a place to attach a chain so you can open it without reaching down inside, too.

@kritiper
That’s what I was referring to.

You want to clog your toilet so you can clean your toilet? What? This question makes no sense.

@longgone Thanks, I had not thought of that. What if I leave the bleach standing in my toilet for a long time, would it decompose into something less harmful?

@capet Unfortunately, I doubt it. Not an expert though. Why don’t you tell us what your challenge is – I’m sure someone will have an idea for a harmless alternative. Personally, I alway try white vinegar first. But there’s lots of options.

@KNOWITALL Thanks, we’re all good. I didn’t say this in the question, but it’s really the clog-and-soak that I’m committed to trying; I’m not so committed to the bleach.

Small amounts of bleach, used quickly for a scrub and flushed immediately, might be ok, but definitely don’t leave it sitting. It’ll damage the enamel inside the toilet. And definitely don’t mix it with anything else, or even use the toilet in it. Bleach, when mixed with so many other common chemicals (including ammonia, which urine contains) can produce a toxic gas. Many people are injured, some even killed, each year from mixing bleach with other, common household chemicals. Personally I would just avoid using bleach altogether.

I’m still not understanding why you want to clog the toilet.

@longgone Thanks, that makes sense. Do you have an idea of whether there is any concentration that is “safe” or “no worse than the rest of the waste stream” or something like that?

If so, I assume that I could consult some kind of reference to determine when the solution is likely to have decomposed sufficiently. I don’t mind letting it sit for a week or two No idea whether that’s enough, or whether there is such a thing as “enough.”

In industrial applications, when they need to work on a pipe but don’t want to or can’t drain the system, they use glorified balloons. Might think about putting a balloon into the pipe and then inflating it to get a good seal. Another option would be to find a solid round rubber ball that would not fit into the hole. It might not be a perfect seal, but would allow you to pour a bucket of cleaning solution in there and keep it in place long enough to be effective.

Man. Soak the rim with bleach via a washcloth. Let it sit for an hour then use a scrub pad to clean. By hand. DO IT!

I always block my toilet by standing in the doorway and order it to ‘stay in there.’

I hate hearing it run. Keeps me awake.

There’s no reason why you’d want to do a permanent clog on a toilet just to clean it. Is there some mischief involved, or a disgruntled tenant who’s moving out and wants to cause some damage? The ultimate remedy will be replacing the toilet and/or snaking out the pipe.

I should have my 7-year-old grandson visit you. He has a talent for clogging the commode!