How to test for mold in pipes?

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iyiyi

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Hi. We live in an apartment complex built about 20 years ago.
We've noticed that black gunk builds up relatively quickly (I would say it is noticeable within a week or less) in one of our toilets (we have two, doesn't seem to be bad anywhere other than the one toilet).
No mold in the tank and only a small amount in corners of shower after a few weeks (seems normal)

It looks like black liquid dripping down the sides of the toilet (mainly on the left side). I forgot to get a photo before cleaning the last time.

This is the bathroom we both shower in daily and it does not have a vent fan to the outside or a window (just one of those cheap fans that blows air around)

Does this mean we have mold in our pipes, or could it just be humidity in the bathroom? The relative humidity in the apartment is usually 45-50%

I am worried there is mold in our drinking water. I have been having quite a few unexplained health issues.

Is there a way to test the water for mold or any other way to get to the bottom of this? Is there a way I could flush or clean the system on my own?

The maintenance and management here is absolutely horrible. Ideally I would need some way to prove there is mold otherwise they won't do anything.
 
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havasu

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First, get your water tested by a reputable company. Mold accumulates when you don't exhaust all the moisture in the air. Can you devise an exhause fan to purge the moisture I believe this is the main issue.
 

Jeff Handy

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Buy these, they work well.

BE5325D4-A02E-4A1E-A200-C4951FC433D5.pngJust drop a tablet into your toilet tank, on the far right side.

You will not have any more black stains.

Leave your bedroom door and bathroom door open whenever you can.
Run the a/c to dehumidify your air.

Open the windows whenever weather permits.
 

Jeff Handy

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PS I have never seen newer apartments that did not have ventilation in the bathrooms.

They often have a master vent system, with a fan on the roof that pulls air from a small grill on the bathroom ceiling.

A vent (or a window) is required by code.
 

iyiyi

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PS I have never seen newer apartments that did not have ventilation in the bathrooms.

They often have a master vent system, with a fan on the roof that pulls air from a small grill on the bathroom ceiling.

A vent (or a window) is required by code.
We definitely do not have a vent to the outside or window. It's a self contained fan that just blows air around. They confirmed this. I'm in NC, maybe it's not code here?

I will probably just start running my dehumidifier every time we shower
 

iyiyi

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First, get your water tested by a reputable company. Mold accumulates when you don't exhaust all the moisture in the air. Can you devise an exhause fan to purge the moisture I believe this is the main issue.
I'm concerned about mold in the pipes, not necessarily in the air. Our relative humidity is consistently less than 50%. I have a dehumidifier to make sure.

Does it sound like mold in the pipes/drinking water could be an issue?
 

Jeff Handy

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No, it does not, IMHO.

Mildew and algae will commonly grow in a toilet bowl.
Clean with Clorox thick gel bowl cleaner.
That also kills spores.

Try leaving the top seat cover open, for more air circulation.

And maybe your tank flapper has a slight leak, which will greatly increase the chance of mold or slime growing on the sides of the bowl.

Try adding a Clorox tablet to the tank, 99% chance your problem will go away, for only a few dollars cost.

The chlorine might wear out the flapper in a few years, changing out a new flapper is about $6.00.
 

havasu

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If you are on municipal water, testing is not necessary. In my opinion, if using well water, you should test it occasionally.
 

iyiyi

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No, it does not, IMHO.

Mildew and algae will commonly grow in a toilet bowl.
Clean with Clorox thick gel bowl cleaner.
That also kills spores.

Try leaving the top seat cover open, for more air circulation.

And maybe your tank flapper has a slight leak, which will greatly increase the chance of mold or slime growing on the sides of the bowl.

Try adding a Clorox tablet to the tank, 99% chance your problem will go away, for only a few dollars cost.

The chlorine might wear out the flapper in a few years, changing out a new flapper is about $6.00.
Thanks, I'm sure the tabs will work, just don't want to fix that problem and ignore it if it's potentially a sign of mold in the pipes that our drinking water comes from
 

iyiyi

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If you are on municipal water, testing is not necessary. In my opinion, if using well water, you should test it occasionally.
We have municipal water. Why is testing not necessary in that case? Couldn't there be mold in the intake water pipes in our apartment building or no?
 

havasu

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Muni water adds chlorine to keep the water supply safe. This stops mold growth. If you have concerns, request a free copy of their last mandatory test results at your water department. Most are proud to show how safe the water is to drink.
 

shlasko53

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Hi. We live in an apartment complex built about 20 years ago.
We've noticed that black gunk builds up relatively quickly (I would say it is noticeable within a week or less) in one of our toilets (we have two, doesn't seem to be bad anywhere other than the one toilet).
No mold in the tank and only a small amount in corners of shower after a few weeks (seems normal)

It looks like black liquid dripping down the sides of the toilet (mainly on the left side). I forgot to get a photo before cleaning the last time.

This is the bathroom we both shower in daily and it does not have a vent fan to the outside or a window (just one of those cheap fans that blows air around)

Does this mean we have mold in our pipes, or could it just be humidity in the bathroom? The relative humidity in the apartment is usually 45-50%

I am worried there is mold in our drinking water. I have been having quite a few unexplained health issues.

Is there a way to test the water for mold or any other way to get to the bottom of this? Is there a way I could flush or clean the system on my own?

The maintenance and management here is absolutely horrible. Ideally I would need some way to prove there is mold otherwise they won't do anything.
Its not uncommon for gunk to build up. The water quality is not optimal. Your water contains minerals. You should use a higher grade of water for drinking.
 

BlueSkyHigh

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Take care and have a great day. I guess I am a little hyper-sensitive at my attempts at humor in today's world and I should keep them off this forum in any event.
 

Hamberg

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We do mold remediation, so JMOFWIW! Mold (not mildew) only grows where there is a food source, which 95% of the time, is dead (drywall cellulose) or dying "organic" material, with moisture present. It will not grow in pipes with water flowing through them! My guess, (sorry @Jeff Handy) is you or someone are using chlorine tablets or putting chlorine in the tank and its dissolving/melting your (cheap) flapper (which I'm guessing is black?) along with the tank seals.
 

PerplexedPlumber

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I don't see a reply about *****lactam, and didn't bother to search, but it sounds like a "lactam" type of antibiotic. Maybe this is used for agricultural water purposes, but not likely for potable water unless it is a treatment by a licensed professional - just guessing.

On whether the water is from a municipal source: if it is ozone or chlorine treated water and the lines are flushed periodically, there shouldn't be mold/mildew originating inside your water lines. If you are on an untreated well system in something like a condo, managed by a homeowners association, the water quality may be worth checking periodically. But if your concern is the mildew that grows on walls or in your toilet or other areas of moisture, possibly from condensate, you are in an area of the country where humidity is common and mildew is transmitted through air. 50% is too high to keep mildew down; 40-45% would be a better target. Once it is present in your environment, it is hard to eliminate, especially from porous surfaces like wood. There are some cleaning products that would be good to use where you may have seen mildew growing in the past. I *think* Formula 409 works for this (check the label) and could be used on walls and other surfaces. Fabric surfaces such as sofas are not as easily cleaned beyond the depth of the surface fabric. Keeping open air movement will be important, like not having "skirts" on beds or sofas. Your air conditioning ducts may have mildew, especially if the house has been vacant for any period of time without air movement. If the return air is also ducted, it may be worth contacting a company that cleans ductwork, if there is a reliable one in your area. However, return air is often not ducted, so an attempt to clean would only impact the supply ducts. If it were me, I would first opt for lowering the humidity setting on the dehumidifier and be sure that all rooms are sufficiently dehumidified and by increasing air movement inside by setting your system to "On" instead of "Auto" or by using a fan. Dehumidification over a long period of time should manage the issue and continued dehumidification should prevent re-emergence.

The Chlorox tabs should help keep the growth down inside the toilet. The tank and the toilet will always be areas that promote growth of bacteria and fungi.

That is relatively recent construction to have not installed ducts for the vents.
 
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Mitchell-DIY-Guy

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If you have a municipal water supply, AND you live in an "occupied apartment" where the water is run periodically through the day, it is highly unlikely that you would have mold or anything else growing "inside" your supply pipes. Not enough [available] oxygen, and there's enough chlorine and other sanitizing additives to the water. When the muni supply is "disturbed" in any way they typically will issue a "boil water alert" until the pipes are flushed.

Surfaces that get wet, outside the pipes (from a leaky fitting or any other drip-drip-drip) that falls on wood or other organic material will indeed get moldy. It's very typical for a toilet to develop mold around the underside of the rim, and at the water line periodically. Get a toilet brush, some cleaner, and it takes a minute to remove and you'll be good for a while.

As a home inspector here in NC, most crawl spaces I go in are festering toxic waste dumps. Often with continual leaks and condensation drips, plenty of oxygen, plenty of wood and organic matter to feast on, and often humidity levels exceeding 90%. Nobody cares since nobody goes into their crawl space. They only care when the problem gets bad enough to destroy equipment or structure.

If you are concerned about the water you drink--install a small RO system for drinking water. That should alleviate your concern about your health at least.
 

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