Bad smell after putting hands/arms in water

[FredFredrickson]

So I have this problem in the past but had retired my hot tub a few years ago and hadn't thought about it until I got a brand new hot tub which I'm using now. Got all the chemicals balanced, 7.4 pH, 8 free chlorine, 40 CYA, 60 TA

Usually at night I'll add enough chlorine to bring it up to 10, and by the time I get to soak the next night it will be down to 8 if I leave heat up, if I bring down the heat for a couple days I can usually get away keeping it between 5-8 a dipping too much between chlorine additions.

Today while putting my arm in to reach the filter for cleaning I noticed as my arm started to dry not immediately but as it dried that there was a funky smell coming from my arm. I was worried that this meant something had gone terribly wrong with my water and was fixing to start a refill when I decide to take a look around on the forums and found somebody else who had witnessed something very similar to me...

Nasty, "rancid" smell in spa water will not go away-- possibly due to very low FC for several days?

It got me to thinking, there's a way to test this water without using my arm, so I got a paper towel and dipped it in the water and then let it dry on my counter. As it's drying on my counter it does not smell at all. This suggests the water itself doesn't really have a smell but it does when it interacts with my skin, I was wondering if anyone had any more insight on this or if there's still something wrong with the water that needs to be addressed?

 

[Mdragger88]

It may be the cc’s created by the fc as it oxidizes contaminates (your body oils etc)
Have u been testing for cc’s? It doesn’t show in your logs.
Also before getting in try to let the tub “air out” a little (aka let the cc’s escape)
Did u do an Ahhsome purge?

 

[FredFredrickson]

It may be the cc’s created by the fc as it oxidizes contaminates (your body oils etc)
Have u been testing for cc’s? It doesn’t show in your logs.
Also before getting in try to let the tub “air out” a little (aka let the cc’s escape)
Did u do an Ahhsome purge?

I did a cleaning rinse when I got it new, with a cleaner I have here but don't remember the name.

I haven't tested for CC recently because the water is only a couple weeks old. I will test today.

 

[Mdragger88]

If it wasn’t Ahhsome- get some & do a purge. You may be surprised what comes out.
You should do this every 4-6 months anyway before you drain & refill so it’s good to have it on hand.

 

[FredFredrickson]

I'll definitely pick some up. As of right now it's a brand new hot tub and 2.5-3 week old water

 

[Roaddogmm]

Ahhsome is great, but I wonder if this is just the effect of chlorine oxidizing your "dirty" arm a bit.

Is 8-10 your chlorine level? Thats on the high side... If you are dosing with dichlor you might find yourself quickly with a high CYA level, I know I did when my tub was new. If you are using dichlor, check the dichlor then bleach sanitizer method pinned to the forum

 

[Newdude]

As of right now it's a brand new hot tub and 2.5-3 week old water

The factories run them to test and then drain them, but don't seem to care about the plumbing. Even if it didnt sit for a while in storage or transit, untreated water can go stagnant in no time.

Now, thats not to say that your plumbing *has* to be nasty, but its the first thing i'd rule out with balanced water.

 

[Mdragger88]

Definitely just a check all the bases kinda thing w/ the Ahhsome. You’re keeping sanitation up splendidly. I have a feeling like as mentioned above - that it’s due to the higher fc level when your arm went in. Sometimes I notice it when i 1st get in if fc is on the high side for my cya. Especially since i just opened the cover & the water is right in my face off gassing.

 

[FredFredrickson]

Ahhsome is great, but I wonder if this is just the effect of chlorine oxidizing your "dirty" arm a bit.

Is 8-10 your chlorine level? Thats on the high side... If you are dosing with dichlor you might find yourself quickly with a high CYA level, I know I did when my tub was new. If you are using dichlor, check the dichlor then bleach sanitizer method pinned to the forum

I add CYA manually so it's pretty consistent @ 40, and we use liquid bleach. For the CYA level, 8fc is a tad high but it gives me a little margin between adding chemicals. If I bring it to 10 at the end of the night, it will be 7-8 by the next soak, and 3-4 after the soak. Seems to work out.

If that smell is oxidizing arm, that would make the most sense.

 

[FredFredrickson]

The factories run them to test and then drain them, but don't seem to care about the plumbing. Even if it didnt sit for a while in storage or transit, untreated water can go stagnant in no time.

Now, thats not to say that your plumbing *has* to be nasty, but its the first thing i'd rule out with balanced water.

I just checked my shed, the initial rinse I did was seaklearspa system flush.

I will pick up ahhsome for the next flush.

 

[Mdragger88]

I just checked my shed, the initial rinse I did was seaklearspa system flush.

I will pick up ahhsome for the next flush.

There are some great write up comparisons between the two products that are eye opening.
Here’s one

Seaklear Vs Ahh-Some Test Results

Here I present results from testing the "Ahh-some" flush product against SeaKlear's "Spa system flush". bottom line: Ahh-some is the clear winner for me, and I won't go near the System Flush stuff anymore -- but read on for specific details. My tub is a good candidate for a flush: Brand new late ...

www.poolspaforum.com

Here’s another

Controlling Biofilms in Hot Tubs and Spas – part 1 - rvdoug.com

Controlling Biofilms in Hot Tubs and Spas - part 1 My first set of experiments Residential Hot Tub and Spa manufacturers, as well as consumers, are becoming more and more aware of the presence and impact of a contamination known as biofilms -- collections of microorganisms that anchor themselves...

rvdoug.com