Stubborn staining under the lip of my toilet bowl

[bizistaken]

Hey everyone - new to the forums (intro'd myself over in the new members section), appreciate any help you can offer in advance!

I really know nothing about plumbing so pardon if I use any incorrect language here, but essentially I've found that under the lip of my toilets where the water flows into the bowl after flushing there is this brown/black-ish stain on the porcelain that I just can't get out no matter what I try.

My problem here is two-fold - I want to:

1. Get rid of the stain on the porcelain, and
2. Determine the most likely cause of the staining to begin with

What you're seeing in the attached picture is just stains, no active substance on the bowl since I've already tried scrubbing it with almost everything. In several different cleaning sessions I've done toilet bowl cleaner, bleach, hydrogen peroxide, vinegar, baking soda, bar keepers friend, and I've used a sponge and a magic eraser to try to get rid of it, and nothing works. It's not even "kind of" coming off and I just need to put in a little more elbow grease - it doesn't seem to be changing at all. Any ideas what I could do to try to remedy this and get rid of the stains?

Secondly, I'd like to know what the most likely source of the issue is. I live in Portland, OR which is known to generally have soft water, which I know doesn't rule out mineral staining, but potentially makes it a less likely cause. It's a newer home, built maybe 5 years ago and we are the first tenants, so it's not like it is an old toilet is super old. I'm concerned it may be mold/mold stains, but I don't recall there being a substantial amount of "gunk" on the toilet that would leave staining this extensive. Does anyone have an idea of what might be the main culprit here?

Thanks again in advance, and if there are any details I've left out that might be helpful, just let me know!

 

[havasu]

Get a pumice stone. It works like magic and will get rid of that quickly.

 

[bizistaken]

I will give that a shot! Any idea what might be the cause of it? I'm trying to figure out if it will be a continuous problem or if there is something from within the rim of the toilet that I need to be worried about.

 

[havasu]

It is usually calcium build up from the water. Once you use a pumice stone, follow up with a good bowl cleaning once a week, until you see it building up again, then use the pumice stone again. I have hard water and we have to to this ritual once every few months.

 

[mark3885]

The darker area around the holes is unglazed clay, the white droplet looking stuff is over spray of the glaze , which won’t scrub off. The brown streaks down the inside of the bowl could be from hard water or poor quality in the manufacture process . I’m assuming this is a low quality toilet due to the poor glazing process. Don’t mean to offend, just my 2 cents.

 

[Wren]

Looks like an unglazed area to me as well.

 

[bizistaken]

Following back up on this thread - thank you all for the comments!

@mark3885 and @Wren - No offense taken, I am currently renting the place I'm in so the toilet was not my choice. Unfortunately, it's also something I don't have control over changing. I did try the pumice stone as suggested by @havasu, but unfortunately had no luck.

This is most definitely a dumb question (I'm new to all this stuff), but what exactly do you mean by glazing here? Are you saying the more in focus brown lines in and around the holes are just unfinished/unglazed and they did a crappy job of applying the finish under the rim?

For context, I've attached a photo of the inside of the tank that has the info on the type of toilet it is.

 

[Twowaxhack]

It’s a cheapo toilet. Real cheap

 

[TomFOhio]

I wish all the brands put the part numbers under the lid or on the tank like that.

 

[Twowaxhack]

I wish all the brands put the part numbers under the lid or on the tank like that.

Totos pretty good about it.

 

[MicEd69]

Following back up on this thread - thank you all for the comments!

@mark3885 and @Wren - No offense taken, I am currently renting the place I'm in so the toilet was not my choice. Unfortunately, it's also something I don't have control over changing. I did try the pumice stone as suggested by @havasu, but unfortunately had no luck.

This is most definitely a dumb question (I'm new to all this stuff), but what exactly do you mean by glazing here? Are you saying the more in focus brown lines in and around the holes are just unfinished/unglazed and they did a crappy job of applying the finish under the rim?

For context, I've attached a photo of the inside of the tank that has the info on the type of toilet it is.

View attachment 35002

Toilets are generally made out of clay, then a glaze is applied and fired in a kiln to make a smooth glass-like surface. You can see the transition between the glazed portion and the non-glazed portion on the tank. The outside of the tank is glazed and very smooth, but the inside of the tank is not glazed and feels like a fine sandpaper. Run your finger over the outside of the tank, then up and over to the inside of the tank, and you can feel where the glazing stops.

In your photo of the underside of the toilet rim, you can see what appears to be areas where the glaze was not fully applied. The areas where the glaze is applied should be smooth to the touch. It is a little difficult to absolutely confirm the poor glazing under the rim, but it sure looks like that is the problem. If you run your finger over the area where there are "stains", it would likely feel like smooth bumps or blisters on a fine grit sandpaper.

As others have said. my guess is this is a cheap toilet with poor quality control by the manufacturer. Not much you can do other than to replace it.

 

[bizistaken]

Thank you all for the additional context! Ideally we'll be out of this place and buying our own home sometime this year, so it won't be an issue then.

In the meantime though, are there are any concerns about the state of the toilet, or it more just that it is lower quality and should get a better option? My concern is whether or not the exposed clay could create issues related to more bacteria/mold growth etc.

Again, I appreciate all the help!

 

[MicEd69]

The nooks, crannies, and unglazed clay would better support bacteria growth, but I doubt this would be any real health issue. The regular use of straight chlorine bleach or a toilet bowl cleaner containing chlorine should provide you a safe toilet.

 

[bizistaken]

Thank you for the advice!

As it relates to the non clay part, the actual grayish faded streaks... any suggestions for how to take care of that? Tried the pumice stone and it didn't really work. And I've tried basically everything else under the sun per my original post.

 

[MicEd69]

I can't tell from the picture, but that could possibly still be another defect from the original manufacturing. The clay could have had a depression or ridge in it and the white glaze is just not be as thick in that area.

If it is a stain, there is a possibility that hydrochloric acid, AKA muriatic acid sold in pool supply houses, would remove it. But if you are not comfortable handling dangerous chemicals, you may not want to risk using acid. The fumes and burns from this acid are quite dangerous. If you are a careful person, and there are no children around, and you feel comfortable using dangerous chemicals, you need to be sure to use nitrile gloves, goggles (or full-face shield even better), and be extremely careful with ventilation. You don't want to breath the fumes, but you don't want a wind tunnel that could blow the fumes or droplets to areas where they could cause damage or injury. You will need to wet a rag with the acid and hold it on the stain for a few minutes. I would advise against scrubbing the area as it could splash acid or throw droplets around the bathroom and/or on your clothes and skin.

After using the acid, I would pour some baking soda into the bowl to neutralize the acid before flushing the toilet. It will foam quite a bit when you pour the baking soda into the acid water in the toilet.