Black flakes from the jets, brown slime, or floating specks that appear only when the jets or microbubble system are running almost always come from residue inside the plumbing lines, not from the tub shell. The fix that works is the published Ella's Bubbles vinegar flush, done exactly as written and repeated if needed, together with a clean pump inlet cover and a few habits that keep the lines from building up again. Bleach is not the answer: it can damage acrylic over time, and it is not part of the Ella's Bubbles cleaning instructions.
What Causes the Flakes and Slime
The air and hydro systems are fully plumbed, so whatever goes into the bath water can travel through the lines. The sources we see most often in support requests are:
- Bath bombs, oils, fragrances, and salts. The printed cleaning instructions ask you to avoid bath bombs because they are hard to clean out and may clog the jet system; the oils, dye, glitter, confetti, and floral material in them are the culprits. Bath oils, fragrances, and salts may be used but are not suggested, because they call for more frequent cleaning of the tub and its plumbing. Our bath products rules article has the full list.
- Standing water in the foot jets. One customer described a faucet that dripped while the tub sat idle, so water collected in the foot jets and turned to mold and mildew between baths. A dripping faucet is worth fixing on its own, and it explains black material floating up when the jets start.
- Long stretches without use. Water left in the lines for weeks gives residue time to build up, so the first run after a break tends to release it.
- Hair and debris at the pump inlet. The pump inlet cover collects hair and debris that can circulate if it is not cleared.
- Mineral deposits. The monthly vinegar flush exists partly to keep mineral deposits and calcification from forming in the system, so skipping it lets scale accumulate.
The Flush That Works: The Published Recipe
Several customers who wrote in had already tried vinegar and still saw debris, usually because the amount, water level, or run time did not match the current instructions. Use exactly this procedure, the same one Ella's Bubbles publishes for first use and monthly maintenance:
- Mix 2 cups of white vinegar with 2 cups of water (a 1:1 mixture).
- Fill the tub with water to one inch above the highest jets, so every jet is submerged.
- Add the vinegar and water mixture to the tub.
- Run the tub for 10 minutes with every system you have on, hydro, air, and microbubble, so the mixture moves through all of the lines.
- Drain the tub completely.
If the water still shows flakes, repeat the same flush. A tub that has sat unused or that has had bath additives in it can take two or three passes, on consecutive days if needed, to run clear. Wipe the jets between runs.
Clean the Pump Inlet Cover
Once a month, and any time you are chasing debris, clear hair and debris from the pump's inlet cover, then wipe it down with a non-abrasive towel and an approved cleaner such as Dawn dish detergent. A clogged inlet can keep releasing material even after a good flush. Hair catchers and drain gaskets are covered in drain plugs, gaskets, and hair catchers.
Let the Built-In Systems Do Their Part
- Ozone sterilization comes with the hydrotherapy massage system and engages automatically whenever the hydro massage runs. It is an eco-friendly, chemical-free disinfectant that helps with hygiene and odor between flushes, though it does not replace the monthly cleaning. See ozone sanitation explained.
- Auto Purge comes with the air jet system. About 20 minutes after you turn the air massage pump off, it starts on its own and runs for 120 seconds, blowing leftover water and bacteria out of the air lines to prevent mold and clogging. You will hear the air system run for about two minutes and then stop by itself; you do not need to wait for it or do anything. Details are in the Auto-Purge article.
This cleaning and maintenance guide walks through how an Ella's Bubbles tub keeps itself clean and what you do on your side. It shows ozone sterilization activating with the hydro jets and Auto Purge clearing the air lines after an air massage, then covers a twice-monthly wipe-down with a non-abrasive cleaner, regular cleaning around the intake screen so it stays free of debris, a caution against bath bombs because their ingredients can damage the pump system, and the monthly vinegar flush. For the flush itself, follow the current published recipe in this article: 2 cups of white vinegar plus 2 cups of water, fill to one inch above the highest jets, run for 10 minutes, then drain.
Habits That Keep the Lines Clean
- Rinse the tub after any bath with Epsom salts, oils, fragrances, or salts. Flushing after every ordinary bath is unnecessary because the systems are plumbed, but additives are the exception.
- Skip bath bombs entirely.
- Keep up the monthly flush and inlet cover cleaning even in months of light use, and flush before the first bath after a long break. The full schedule is in cleaning and monthly maintenance.
- Have any dripping faucet or hand shower looked at so water is not sitting in the foot jets.
What Not to Use
- No bleach. When customers have asked about using bleach, our support team has explained that it can damage acrylic over time and pointed them to the 1:1 vinegar and water flush instead.
- No abrasive cleaners or pads. They scratch the acrylic. Stubborn construction debris on the shell can be handled with denatured alcohol or Clorox Soft Scrub, which is guidance for the shell, not the jet lines. The approved list is in approved cleaners and chemicals to avoid.
Common Questions
Dark flakes appear when I run the jets even after vinegar. What am I missing?
Brown slime forms every time. Should I use bleach?
The tub sat unused and now mold floats in the water.
Specks come out of the microbubble port.
There was a black, grease-like film on the walls after draining.
Do I need to flush after every bath?
What causes the debris in the first place?
When to Contact Us
If debris keeps appearing after two or three correct flushes, take photos of what comes out and of the affected jets or port, note your model and serial number, and open a ticket at ellasbubbles.com/support or call (800) 480-6850. We will be glad to help with anything specific to your model.