Possible causes: 1) Aging failure of marble adhesive. 2) Lack of support during installation.

Solutions: 1) Clean the old adhesive then reapply the marble adhesive for fixation. Then use wooden sticks for temporary support until the adhesive is dry. 2) Install dedicated metal supports for under-mount sinks to enhance load stability.

Possible causes: 1) Poor glaze quality (low-temperature firing: This results in rough, porous glaze on inferior ceramics, allowing stains to seep in; uneven glazing: Thin or incomplete glaze, especially inside drainage pipes, leads to residue build-up; high water absorption rate: Ceramics with absorption rates >0.5% have stronger stain retention). 2) Improper cleaning methods (long-term use of hard brushes, acidic detergents [e.g., toilet bowl cleaners] will wear the surface, increasing stains; failure to timely clean urine scales and mineral deposits leads to mineral accumulation; the pipeline design is flawed; the flushing strength is insufficient or the bend design is improper, resulting in backflow; uncoated pipe interiors encourage dirt adhesion and bacterial growth, which also leads to foul odors). 3) Bacterial and microorganism growth (humid environments easily breed Serratia marcescens [red stains], E. coli (yellow urine scale), etc.; long periods without disinfection cause residual microorganisms, forming stubborn stains.)

Solutions: 1) Purchase high-quality ceramic products (check the manufacturing processes: Choose ceramics fired at high temperatures [above 1280°C], which typically have a smooth, dense glaze; feel the surface, which should be fine-textured and free of grit; ensure the pipe interiors are also glazed; for stain resistance, draw a line with ink and flush: The less residue, the better the performance). 2) Routine cleaning and maintenance (gentle cleaning: Use a soft sponge + neutral detergent [e.g., baking soda, white vinegar] for regular washing; disinfection and sterilization: Soak in chlorine-based disinfectant [e.g., 84 disinfectant] for ten minutes weekly to kill bacteria). 3) Stubborn stains (scale: Soak in white vinegar then scrub; urine scale: Apply a paste of baking soda and hydrogen peroxide, leave it for 30 minutes, and then scrub; red/yellow stains: Use special toilet cleaning gel [e.g., UPO no-scrub version] and let it sit for 60 seconds before flushing). 4) Pipe maintenance (unclogging the pipe: Clear pipes every three months with pipe cleaners to avoid dirt build-up; odor removal: Place a toilet cleaner in the tank to form a protective film and continuously inhibit bacteria.)

1) Keep surfaces dry: Wipe down tops and toilet seats promptly after use to reduce water stains and residue.

2) Upgrade equipment: Consider a smart toilet (with self-cleaning glaze + UV sterilization) or odor-proof flange to reduce stains from the source.

3) Precautions: 1. Avoid using steel wool, scouring powders, and other hard tools to prevent scratching the glaze. 2. If heavy staining cannot be removed, the ceramic may be aging. Consider replacing it with a high-quality product. 3. Choosing high-quality ceramics, cleaning properly, and conducting regular maintenance

can significantly reduce staining and keep your bathroom clean and hygienic.

1) Cleaning: Use citric acid or white vinegar to regularly remove scale. Avoid scratches from hard objects.

2) Anti-clogging: Install a filter in the basin to intercept hair. Do not throw anything other than toilet paper in the toilet.

3) Inspection: Check the sealing glue and drainage components every six months and replace aging parts promptly. For complex issues (e.g., wall-mounted toilet repairs, smart lid malfunctions), contact FAENZA after-sales service for professional support.