Asked on Apr 25, 2012

My Jacuzzi tub is spitting out black specs when I turn on the jets. I've done everything I can think of bleach,etc. Help

Renee B
by Renee B

Help - does anyone have advice on how to clean bathtub jets?

  23 answers
  • 3po3 3po3 on Apr 25, 2012
    This is not uncommon. Have you tried actually using a Jacuzzi tub cleaner? They are available at the big box home improvement stores.
  • Renee B Renee B on Apr 26, 2012
    Actually I didn't know there was a cleaner on the market for that. Thanks...I'll give it a try.
  • KMS Woodworks KMS Woodworks on Apr 26, 2012
    do you know if these black "specks" are "soiling" or could they be "gasket" type rubber bits? If they are bits of rubber you may be losing some critical "sealing parts" of the pump assembly. Old rubber bits tend to dry out an crack, eventually they can fail. I would take a peek inside the service access panel to inspect the pump, fittings and plumbing for leaks. Better to catch a leak early then later after prolonged water damage can ruin sub flooring etc.
  • Jacuzzi tubs can discharge all sorts of stuff. They tend to build up a bio film that even bleach will not remove. What is happening is soap scum, hair, skin cells and a bunch of other things I will not say builds up within the pipes even after you drain the tub out. The result is as it sits there it begins to develop a film that grows. If you leave the tub empty for several weeks this film dries out and begins to flake off the next time you use the tub. Using bleach does not kill this bacteria as one would think, but it does loosen some of the surface material and cause it to flake off every time you use the tub. You need to heavily chlorinate the tub and pipes. let it sit in the tub for several hours while the jets operate. Be sure to ventilate the tub area when your doing this as the chlorine gas will become quite powerful. Also using Algacide that is used for black Alga in swimming pools will also be required to kill off this bacteria as bleach or chlorine by itself is not enough. You can get that at any pool supply along with the chlorine. Bleach in a bottle is not strong enough to use alone. Hope this helps.
    • Karen Karen on Oct 07, 2018

      We have the black chunks coming out when using the jets. My husband is trying to tell me if you don't turn the jets on its ok. He keeps getting skin rashes and won't listen who does that? Can the professional jet cleaning stuff really help? I use white vinegar to flush out the jets with hot water.

  • Renee B Renee B on May 07, 2012
    Wow, now I think that might do it. We have a swimming pool so I think we have the algae killer...I'll go get a small thing of chlorine from the pool store. We have a salt system in our back yard pool...I definitely will share this with my husband. I hope it works...I love my tub, but the gunk has gotten me a little grossed out. :)
  • Here is one of many links on this topic. If you think the gunk has you grossed out. Do not read it.
    • Oliva Oliva on Jun 25, 2020

      Terrific article, courtesy of Woodbridge Environmental's post !

      I will never purchase a home with a jetted tub, nor use them while vacationing, as too many friends have complained of these issues from jetted tubs in their homes.

  • Renee B Renee B on May 09, 2012
    Thanks to Woodbridge, I have read a couple of your articles and there are very interesting indeed. I purchased today...a product that is safe and suppose to clear out the gunk from the pipes. It's called AAAh-Spa. I did a little research and read the reviews and found them to be reliable. Plus it's safe for septic systems. I will post with the results, I should get the product on Friday. Thanks again.
  • Renee B Renee B on May 09, 2012
    Meant to say they are very interesting... typo. oops.
  • Just be sure they warrant not damaging any seals on the tub. From my understanding of this topic, nothing even regular cleaning after each use prevents this bacteria from forming. Some test results showed regular use of a tub, which did not have time to dry out between uses when the left over gunk would have time to dry out. Showed higher levels over time of airborne bacteria in the air that was typically found in the pipes when swabbed and tested. Jacuzzi brand tubs were sued several years ago because of this very issue. Not sure what resulted as I did not follow it to closely, but what ever you do, clean, clean, clean. every time you use it.
  • Georgette B Georgette B on May 15, 2012
    use cascade dish washing powder
  • Grant Thomasson Grant Thomasson on Dec 16, 2014
    Your theory of the biofilm drying out and coming off as flakes isn't true. I have the same flake problem on initial use, after completely draining the tub, and my tub is used Tues/Wed/Thur. Renee B - how did the AAAh-Spa work.
  • SashaDelToro SashaDelToro on Apr 24, 2017

    Don't use bleach! I learned the hard way, as it corroded my rubber seals in my whirlpool tub. After that costly repair, I found a product called Plumb Clean on the website. It has worked for me and got rid of the yucky black flakes. I was told that the water settles in the plumb lines of the whirlpool tub and grows mold and bacteria and that's what you see sometimes when you run your tub. Gross! I haven't seen any of that since I started using Plumb Clean over a year ago.

  • Olive Greenz Olive Greenz on Apr 25, 2017

    I learned this while living in Japan. Always take a shower first to get clean. The tub is for making you feel relaxed while reading, listening to music or soaking your joints if you have that problem. There is a sponge thing you can buy that floats on the water and grabs hold of any grungy stuff.

  • Have your hot water tank cleaned and inspected.

  • Susan Lucas Susan Lucas on Apr 25, 2017

    When I had a tub I use to use Tang Drink Mix (read about it somewhere). It worked well was cheap and the odor wasn't bad! Fill the tub add tang run the jets and then drain and rinse with clear water (and run through the jets). Cleaned it great and as my kids used the tub too I wasn't worried that their delicate skin was absorbing harmful chemicals!

  • Karen P Karen P on Jul 04, 2019

    I have little black beads in my jacuzzi and I don’t have the jets on. When you rub the beads that are like black grease. What could that be?

    • See 2 previous
    • Rachel Rachel on Mar 25, 2023

      Sorry this response is years old, I just wanted to say something about the black “oily/smears when touched” black spots. I have found out through water testing and also experiments where I bring samples into work that the problem is actually Manganese. After it builds up, it will almost seem gelatinous and it really will stain anything. I live in an area of Arkansas called Hot Springs village and apparently there is an “acceptable amount” of this that will pass water inspection, but when I noticed that using water bottles to fill up my animals drinking bowls and not only would those greasy spots stay in the plastic water bottle, it started to stay on stainless steal (and this is after scrubbing everything everytime, no exceptions). So long story short they say manganese buildup won’t hurt you, however I won’t bathe or shower in it or drink it, if it does what I have seen it do, then no thanks I don’t need it! A simple water filter on shower and everything else has made it disappear but remembering to change often and the cost does become annoying

  • Shelly Caraway-Kominczak Shelly Caraway-Kominczak on Mar 08, 2020

    Same here...Black hard chunks and black oil/grease consistency when rubbed. Hot tub is all of a sudden loud and sounds almost grinding? What could this be?

    • Grant Grant on Jun 24, 2020


      We have the same problem. I was wondering how old your tubs were. Mine is 5 years. I read somewhere the average lifespan of a heater is 5 years. Perhaps something is breaking down inside?

  • Cathy Driskill Mebes Cathy Driskill Mebes on Jan 31, 2021

    Any updates here? Bought a used hot tub and black tiny rocks or particles sink. Please help

  • Lydia Lydia on Aug 22, 2021

    I had this problem with the hot water in my bathtub. It was the cartridge in the hot water handle that had deteriorated. Replaced it with a new one bought on Amazon and problem was fixed.

  • Anet Anet on Jan 19, 2022

    It is biofilm. A combination of mold, mildew, skin flakes etc. You need to clean your whirlpool tub. Just Google it because there’s a lot of different ways and chemicals you can use. Vinegar being the most popular one.

  • Alison Alison on May 05, 2022

    When I bought my tub I was told to fill it with cold water and pop in two Milton sterilising tablets once a week to keep it clean. Certainly seems to work.

  • Mogie Mogie on Apr 03, 2023

    First, drain the water from the tub, then add a cleaning agent, turn the jets on and allow them to run for 15 minutes. Drain the water below the jets, wipe down the tub, and repeat if necessary. If black flakes persist, remove jets from the tub to clean out mold.

  • Mold may be building up in the jets. Try spraying them with vinegar and if that doesn't work, they may have to be removed for deep cleaning.