Why is White Slime in Bathroom Sink Drain?

Microorganisms like bacteria and fungus grow inside or around the bathroom sink drains because of the water and moisture and form a biofilm, also called white slime. This white material layer causes diseases and smells and affects the overall working of the sink.

Why is White Slime in Bathroom Sink Drain? The white slime in the bathroom sink drain is because of the mineral and limescale deposits, food sources in drains, body oils, grease layers, excessive moisture, and clogging of the drain pipes.

Bacteria and other microorganisms multiply into hundreds and form colonies around the sink drain and pipes, which causes different problems in the drainage system. However, do not panic if you observe a white biofilm layer on the sink surface or mucous substance because it is a common problem that many people face.

Why is there white slime in my bathroom sink drain?

There are many reasons for the white slime in your bathroom sink drains, and some of those reasons are listed below.

Mineral and limescale deposits

As we know, the bathroom water supply system uses hard water in the toilet, sink, shower, and bathtub faucets, and the hard water supply causes different problems inside the bathroom drains.

One of the reasons for having the white slime layer or white substance is mineral and limescale buildup in the drain, as it can grow faster around the limescale deposits.

The calcium, magnesium, lime, iron, and other compounds in hard water form deposits there, which attract the bacteria and fungus to grow and thrive.

The microorganisms in white slime can attach themselves to the sink surface, and the limescale deposits make the surface rough and more favorable for the bacteria to cling to this surface.

Food sources in the sink drain

Products like shampoo, soap, toothpaste, and makeup products are more like food sources for such microorganisms to grow and survive in the sink drains.

The presence of such products can enhance the environmental need for white slime, as it needs a proper food source to increase its colonies.

You use soap, deodorants, shampoo, hand wash, and face wash to do different business in the sink bowl, and some of those food sources for white slime bacteria can remain there.

This will cause the slime to propagate in the sink drains and make its way to clog and smell around it.

Body oils and grease layers

You can drop the body oils or greasy products in the sink, or the pet in the house can open the oil bottle and drop it into the sink while you are not around.

These oily and greasy products can cause the white slime to accumulate there, as the oil and water cannot mix and remain floating on the water.

Plumbers recommend avoiding the oils and grease used in the sink drains to keep the sewage and the plumbing system working efficiently.

Excessive water and moisture

Water and moisture are one of the main reasons for bacteria and fungus in the drainage system.

The water inside the drains remains in the pipe for a long time, and the long-term exposure to the stagnant water in the pipes causes the slime to accumulate and grow.

The microorganism clings to the pipes and begins to reproduce and multiply into thousands of colonies and slime layers, which also causes clogging and smell in the pipes.

Sink surface material

Different manufacturers use different materials for sink manufacturing; for example, some have porous surfaces, while others have polished and non-porous surfaces.

The growth of white slime on the surface or around the drains, faucets, and other components can be more for some materials than others.

For example, rubber washers are more prone to slime accumulation than ceramic and silicone material washers. This is because the chances of bacteria and other microorganisms attaching to the porous surfaces are more than non-porous surface materials.

Broken bathroom sink

Cracks around the edges and base of the bathroom sink can cause the water to seep and white slime to grow around the crack surfaces.

The damaged pipes or traps also cause it to present inside the drainage system, and you have to face a worse situation if you do not repair the cracked pipes.

The rough surfaces or the unpolished sink surfaces are susceptible to gathering fungus and bacteria, and you will hesitate to use the sink because of the biofilm layer around it.

Clogged drain pipes

The drain pipes can get clogged because of rust, corrosion, mineral buildup, or oily products. The white slime inside the drains is a sign that the drainage system is clogged, and you need to clean it without delaying further.

The clogged pipes offer the bacteria a good food source, and it will form a slime layer, which can increase the severity of the situation and causes flooding in the bathroom.

How can you remove the white slime in the bathroom sink drain?

You can use different techniques to remove the white slime in bathroom sink drains, as explained here.

Use vinegar and baking soda

Vinegar and baking soda are the natural drain cleaner, and the solution of these two products can react to break the slime from the pipes.

The solution has anti-bacterial properties, which can wash away the mucous material without causing damage to the sink.

Pour one to two cups of baking soda and three to four cups of vinegar into the drain, depending on the severity of the slime accumulation. Let it sit for 15-20 minutes, and pour hot water to wash away all the residues and bacterial colonies.

Commercial cleaners

You can select a commercial cleaner for removing the white slime if the baking soda and vinegar do not work to remove it.

Ensure the commercial cleaner is safe for the sink drains and does not include highly toxic chemicals that can affect your skin while applying it.

It is better to wear a mask and hand gloves before applying such products and read the label carefully to understand the procedure. Let the cleaner stay 3-5 minutes, as mentioned on the packing, and pour warm water to remove it completely.

Ventilate the bathroom atmosphere

Bacteria and fungi are attracted to moist and damp environments, like stagnant water, dirty places, and humidity.

Proper ventilation in the bathroom can reduce bacterial and fungal growth and minimize the chances of white slime in the sink surface and drains.

Open the windows and turn on the exhaust fan after a hot shower to remove the high moisture level from this place. A proper vent system in the drain can also reduce the chances of slime in the sink pipes.

Regular cleaning

Regular cleaning can keep the microorganisms at bay and the sink in good condition. You can clean them using a mild cleaning product daily, or some people pour bleach there to remove the white slime.

Professional plumbers recommend less use of bleach in the sink drains because bleach can damage the PVC pipes and is not safe to use daily.

Clean the surface with a soft cloth after cleaning it to remove the moisture and avoid bacterial growth there. You can pour hot water daily in the sink drains to keep them clean and clog-free.

Replace the bathroom sink

It is better to replace the bathroom sink and its drain if the surface has many cracks or there is leakage in the pipes because this causes white slime around or inside them.

You can select a high-polished material for a sink that will not allow water and bacteria to stand, and high-quality PVC pipes are less prone to cracks and leakage. 

The wider pipes have fewer chances to accumulate white slime if cleaned correctly and after a few days because it allows the material to flow down the drains.

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