MPS impact on CC

[dankasprick83]

Hey all,

Learning a ton here. Love it.

Still seeming to find conflicting information regarding MPS and it's ability to impact CC (apart from it potentially interfering with test results).

I saw this quote on a previous thread on the same topic, " Use a combination of MPS and chlorine in the off-hours to try to bring the CCs down to a manageable level. This will require some trial and error to figure out."

Does MPS lower CC in a system that is using a dichlor/bleach system?
If not, how does one go about lowering elevated CC in such a system? Is there a way to do this aside from water change? If I've understood correctly it sounds like by performing a chlorine shock with bleach there is some potential for reduction of CC but I'm trying to get a grasp on how that mechanism works. I'd picture the chlorine shock oxidizing all of the potential substances and organics within the system that are eligible for oxidation, but wouldn't this just drive CC up even higher in the short run? Is the idea that it drives it up higher in the short run but then the CC's naturally dissipate and there is a reduced rate of CC accumulation but everything was oxidized during the shock?

Appreciate any insight you all might have. I'm a long time hot tub user who has failed to find good answers to these questions over many years and I finally have hope I'll get a good answer.

Dan

 

[JoyfulNoise]

In a very basic sense, chlorine will oxidize simple amines (ammonia and urea) and complex amines (creatinine, etc) into chloramines and then finally into nitrogen, nitrates, and carbon dioxide. However, chlorine can also combine with other organic compounds creating haloforms (chlorinated organics) that cannot be further oxidized by chlorine at any reasonable chlorine levels. This is what creates persistent CCs in hot tub waters. These compounds can resist oxidation by MPS as well and so the only viable option is to dump the hot tub water and start over. Not all CCs are measurable with a test kit and so once you start seeing persistent CC values, it’s time to dump the tub. MPS, when used appropriately, can maybe buy you a little more time but ultimately CCs will build up. Since the cost of MPS is not cheap and it’s interference in testing is a nuisance, TFP doesn’t really recommend it’s use.

Simply clean your plumbing with Ahhsome purges and use the Dichlor-then-bleach method to maintain the tub. You should be able to get 2-3 months between water changes and that’s probably the best you can do.

 

[JamesW]

Is the MPS somehow causing false readings 24h later on my Taylor test kit (I was under the impression it would have dissipated by then)?

MPS will read as CC for a while.

I don't know the exact time but you should expect it to last for a while.

There is a specific reagent to remove the interference.

 

[dankasprick83]

In a very basic sense, chlorine will oxidize simple amines (ammonia and urea) and complex amines (creatinine, etc) into chloramines and then finally into nitrogen, nitrates, and carbon dioxide. However, chlorine can also combine with other organic compounds creating haloforms (chlorinated organics) that cannot be further oxidized by chlorine at any reasonable chlorine levels. This is what creates persistent CCs in hot tub waters. These compounds can resist oxidation by MPS as well and so the only viable option is to dump the hot tub water and start over. Not all CCs are measurable with a test kit and so once you start seeing persistent CC values, it’s time to dump the tub. MPS, when used appropriately, can maybe buy you a little more time but ultimately CCs will build up. Since the cost of MPS is not cheap and it’s interference in testing is a nuisance, TFP doesn’t really recommend it’s use.

Simply clean your plumbing with Ahhsome purges and use the Dichlor-then-bleach method to maintain the tub. You should be able to get 2-3 months between water changes and that’s probably the best you can do.

Thanks. That's very helpful.

 

[JamesW]

395 Gallon Master Spa LSX 850 with circ pump, EcoPur mineral stick, and ozonator.

What ozonator do you have?

 

[phonedave]

In a very basic sense, chlorine will oxidize simple amines (ammonia and urea) and complex amines (creatinine, etc) into chloramines and then finally into nitrogen, nitrates, and carbon dioxide. However, chlorine can also combine with other organic compounds creating haloforms (chlorinated organics) that cannot be further oxidized by chlorine at any reasonable chlorine levels. This is what creates persistent CCs in hot tub waters. These compounds can resist oxidation by MPS as well and so the only viable option is to dump the hot tub water and start over. Not all CCs are measurable with a test kit and so once you start seeing persistent CC values, it’s time to dump the tub. MPS, when used appropriately, can maybe buy you a little more time but ultimately CCs will build up. Since the cost of MPS is not cheap and it’s interference in testing is a nuisance, TFP doesn’t really recommend it’s use.

Simply clean your plumbing with Ahhsome purges and use the Dichlor-then-bleach method to maintain the tub. You should be able to get 2-3 months between water changes and that’s probably the best you can do.

In addition to the above, how long you can go between water changes is dependent on how much "stuff" gets into your tub.

Shower before using the tub, don't spill drinks into the tub, don't drop food into the tub, etc. and you will go longer between changes. Your bather load will also impact the time between changes.

Finally, open your cover for 10 min or so before testing, there are volatile compounds that will escape.