Excessive Spa Foaming

May 31, 2013
Manchester NH
Looking for some help with excessive foam on my hot tub, thanks in advance

Marquis 390 gallon hot tub. Outdoor, new england, always covered except when in use.

We are having excessive foam with air venturis open, no problem when jets on / venturis closed.

tested water, changed water, added CC to get CH up to 150, tested water, complete water change again!

Still foaming, and it never used to foam like this. I suspected a kid foam prank, but with the two water changes and the foam level did not get any better or worse, I can't really figure this one out. I am used to the foam gradually increasing over time due to small amounts of detergent in bathing suits, but this is a large amount of foam, from day 1 of the water change to day 30.

My well has a softener to remove iron and manganese.

I never had to increase the CH of the hot tub in the past to stop foam, but decided to try it this time, to no avail. I added CC to get the CH up to 150 the last two water changes, both which were done in the past month in order to try to stop the foam issue.

Here are the current numbers:

FC 4.0
CC 0.0
pH 7.6
CYA 0-10 - I added 2 tbs of Dichlor so far to this water change, starting 2 days ago. Not much CYA yet.
TA 70
CH 150

I normally use Great Value (Walmart) concentrated bleach (around 8.25%) and only need to use some bleach and do a very small amount of pH balancing over the 2-3 months that the water stays in the tub until the next water change. I have not had to add anything else to the tub in 2 years of using this method until the foam showed up 2 months ago. At that point I tried increasing the CH and then changing the water. Still foaming...

Any ideas much appreciated!!



Silver Supporter
LifeTime Supporter
Jun 22, 2014
Houston, Texas
you know, our spa foams too. We just got it a couple weeks ago. it's not so bad when the pumps are on low but you turn it up and yikes! we're using bromine. My husband tests it and says it's okay. Ofc I have nothing to back that up and show you!


TFP Guide
In The Industry
May 14, 2007
New Brunswick Canada
Yep, that's the culprit. On one hand though, that foam looks pretty clean, your pipes will be clean as a whistle for winter. I would suggest you drain it, then refill it and rinse and drain again.


LifeTime Supporter
TFP Guide
May 22, 2013
Hudson, WI
I don't know "Easy-pour" but that sure sounds like "Splash-less" with a new name and YES ...... it does foam. Let me check the Wamart web site.
Or turn everything on (blower too) and see if you can handle all the foam as it will wear off.


TFP Expert
Feb 3, 2014
Central Minnesota
Any bleach that is splashless or easy pour will have added surfactants. Surfactants do a great job of increasing the viscosity of a liquid to make it thicker and less likely to splatter and splash. However, these surfactants will also cause lots of foaming. It's a bit like adding both bleach and dishwashing liquid to your pool at the same time with these products. Spa decontamination products such as Ahh-Some contain powerful surfactants to disrupt biofilms and other residues in spa plumbing and can be very useful for decontamination.

The other source of foaming if it's not a splashless bleach related incident can be low CH levels or organics contamination.


LifeTime Supporter
TFP Guide
May 22, 2013
Hudson, WI
Either draining and refilling or running it enough to use up the ingredient causing the foam are your choices.

Have you tried using a regular spa anti-foam agent and if so did it do any good ??
May 31, 2013
Manchester NH
thanks all. That easy pour bleach was definitely the culprit. 3 water changes and switching back to regular bleach and then 3 weeks of diminishing foam seem to have gotten us back to normal.

Kiss4, the anti foam did absolutely zero good against these bubbles and I agree I don't like adding it if I don't have to. It went out with the last water change.

on the bright side yes the spa is quite clean!