What does that do exactly?

Not necessary, the sewer pipe is placed horizontally, and the sewer pipe is not 100% filled with liquid, so water cannot be reached on the top part of pipe, if there is a leaking area, sewer gas can leak into the toilet room without flood.

Since sewer device is already in placed, it filled with water and the edge of connection between device and pipe are sealed well, but I can still smell methane, so there are only 2 potential sources of methane:

2) Bacteria on the tiles
3) Leaking gas from unknown location

Drano works for pipe, not the tiles, I would go to clean the tiles again for 20 minutes and blushing the tiles' surface instead of 10 minutes, should acidic solution be appropriated on tiles? If I can still smell, then would it be confirmed that there is a leaking gas within toilet? which already excluding sewer pipe and tiles (2 potentials area).  I need to confirm this 2 issues before doing next step.

For leaking gas from unknown location, I would contact owner and call assistance to fill any potential leaking area within toilet with visual inspection.

Cleaning the debris is not practical with rental room, since it costs money for fixing it, so sealing any leaking area under visual inspection would be a lower cost approach.

Do you have any suggestions?
Thanks, to everyone very much for any suggestions (^v^)


 

It works like a U-Pipe








Thanks, to everyone very much for any suggestions (^v^)

Cool invention


The tiles look clean in that photo, so let's cancel that from the list. If there was bacteria on the tile, it would not produce methane because methane-producing bacteria die in the presence of oxygen. That's why they're found deep within our digestive tract, where oxygen levels are low.


If you don't have Drano available, best to call a plumber. He'll have the snake tool to diagnose the issue better. I think it's better than having to go buy all the tools yourself, as it might be expensive.

In terms of the gas leak, it's not "impossible". Natural gas used to heat the home consists of mostly methane anyway. However, the smell of natural gas is somewhat pleasant to people. Methane produced my bacteria or rotting substances smell bad because it's mixed with other gases/compounds that make it smell terrible. There's a noticeable difference between sewage and pure natural gas.

I place a piece of toilet paper on the floor and fill it with urine stone remover for 10 minutes and clean floor with water, after 2 day monitoring, there is less smell at this moment, how can you explain this result? the smell of methane is somehow related to tiles.

Do you have any suggestions?
Thanks, to everyone very much for any suggestions (^v^)

Does the urine remover have a scent of its own? Is it a liquid or solid?

I don't try to smell it, since urine stone remover is highly concentrated acidic solution.

I would go to clean the tiles again for 20 minutes and blushing the tiles' surface instead of 10 minutes, I would cover more potential flat surface instead of floor alone, any comments?

Thanks, to everyone very much for any suggestions (^v^)

I'm trying to understand what "urine remover" is, that's why I asked. You said it's an acid, so it's most likely a liquid.

In my life I've never heard of smelly tiles, that's why I think it's impossible. Tiles are made of stone, ceramic material; they're not permeable, nor do they leak through. Underneath the tile is plaster, and likely concrete -- two very thick barriers to gas leaks.


This is not indicative of bacterial growth. Bacteria cannot produce methane in an oxygenated zone. Methanogens are oxygen-fearing organisms.

When you look into concrete under microscope, there are many holes on surface, which can store a lot of dirt, which is the foods for bacteria.  

Before applying acidic solution, methane smell is stronger than after acidic treatment.  I keep the same interior condition on comparing before and after treatment.
If it is not related to bacteria, how to explain this results? where do methane come from?

Do you have any suggestions?
Thanks, to everyone very much for any suggestions (^v^)

Most tiles are coated with epoxy, a laminate substance that prevents this sort of thing, so I'm not sure.

I'm assuming the smell of the acid is masking the smell.

Please answer is, does the "methane" smell have the scent of sewage?

Please see the tile condition, it seems that very very strong acid had been applied on tides, the edge is eroded.



 
I cannot confirm on the scent of sewage, since I don't know without comparsion, but it is methane, it is 8 am, and I still smell the methane (less intensive after acidic treatment).  

I don't understand on how the smell of the acid is masking the smell of methane, since I cannot smell the acid at this moment, my nose is sensitive.

If methane come from leaking, it should be the same intensive, but the smell is less intensive as comparing before acidic treatment, I guess that come from bacteria, do bacteria grow fast within 13 hours? I finish UV Light treatment at 7 pm last night.

Do you have any suggestions?
Thanks, to everyone very much for any suggestions (^v^)

@oemBiology, could you answer the question


Is it "sewage" scented?

Smell like "sewage" scented, it is 8:00 - 8:30 am, people use a lot of water during this period before work, sewage gas would easily down to lower floor due to pressure, this period of occurrence is consistence.

Thanks, to everyone very much for any suggestions (^v^)

Could it be the u-pipe from the sink found within the bathroom? Have you examined that part?

If sewage, I don't think it's a leak