Shocking questions about MPS

ayeti

0
Nov 17, 2015
5
Northern Virginia
Hi again folks :wave:

To review I have a small (the latest size estimate is 170 gallons) older spa in the basement. I have a simple hang the electrodes over the edge SWG system on hand and it will be put in very soon (perhaps tonight).

My wife and daughter both have asthma / respiratory issues + very sensitive noses. My daughter recently had an asthma attack after being in the hot tub room with the cover off and FC of around 4. Additionally the whole house smelled of chlorine during a recent shock with FC = 11 despite the cover being on and the hot tub room vent fans being left on 24x7. I'm clearly going to have to do a much better job of controlling chlorine smells.

In that vein I want to use MPS as the primary after soak treatment / shock and use dichlor and bleach only when there is a problem. I you folks have any experience / insight on the following I would appreciate hearing it:

1. What is the most reliable way to test if there is residual MPS left over after shocking? Does Taylor (or other test manufacturers) make a kit explicitly for it? What are safe levels of MSP with chlorine present in the hot tub (I intend to routinely run CYA of about 20 and fc of around 2).

2. If I overdose the spa with MPS will it bring down my free chlorine? I am especially concerned about it bringing FC down to unsafe levels.

3. Is there anything that will remove excessive MPS in the case of overdosing? How long does it take to leave the system on its own?

4. Do I have to achieve a minimum level of MPS in order to oxidise waste and / or split up the combined chlorine or can I give the system repeated small doses until the CC drops?

5. Are there other things / "gotchas" to MPS shocking that I should know about?

Thank you in advance for your help!

-Andrew
 
So after posting this I discovered that when I replaced the vent fan motor in 2011 I put it in wrong causing it to not blow air out (the squirrel cage style blower was spinning backwards!). When I turned the motor around the motor started overheating - I'm not sure if the bearings went bad in the intervening years or if the replacement motor was physically the right size but didn't meet specs in some other way... So the spa is sitting empty for now while the replacement motor makes its way to me...

I think I would still prefer to use MPS for the routine shocking through, does anybody here have experience with it?
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.