new hot tub owner....

Jump to latest Follow Reply
G

GuinnessPhish

0
Jul 10, 2012
438
Herndon, VA
I've gotten everything under control with the pool, thanks to you all, and now I'm ready to get the hot tub in shape.


Not really sure where to begin....where is the "hot tub school"?;-)



Hot tub is a 500 gallon hot tub, which has been using bromine as a sanitizer, but I haven't added any since I moved in about three weeks ago.

Knowing this, what should my first step be? Test the water? Don't bother using the chlorine test, since bromine was being used?
 
Start off by testing the water. I assume since you have the pool under control you have a good test kit. Chlorine and Bromine test is conducted the same way. Depending on test results as to whether you will have anything to contend with.

Also, something I learned the hard way about starting up with bromine. There is a big difference between the bromine you startup with and the bromine you sanitize with. On startup you will need a concentrated form of Sodium Bromide that is near 100%. The Sodium Bromide you use to sanitize with is about 15% and is mostly Sodium Dichlor (Chlorine). I battled several weeks and a lot of reading on this site before I figured this out!

I'm new but, hope I helped a bit:)
 
how-do-i-use-bromine-in-my-spa-or-pool-t102.html

If you need a "spa calculator", Pool Pal on Android will tell you how much chlorine (or any other oxidizer) you need to get your bromine (not the bromide reserve/bank) to the desired level.

The problem is, I made it and I haven't gotten any feedback from anyone on it's accuracy (my spa is connected to my pool, I don't use bromine).

So if you get a chance... I really need a guinea pig :)
 
Anyone have any idea how much a spa service would charge to drain, possibly clean, refill and balance a hot tub? At this point, dealing with shocking my pool and learning about the pool, I'm a little overwhelmed with trying to get up to speed on the hot tub as well....
 
Based on my reading here, I added 1 oz of dichlor on 8/9 at 9 pm.


I didn't get to add more dichlor until this morning, when I mistakenly added 2 oz (4 tablespoons) to the hot tub.

This should bring CYA up to 22.8, right?

My FC was 0 this morning before I added the dichlor. Did I add way too much dichlor? What should I do?
 
The Pool Calculator will answer those questions. 3 ounces of Dichlor in 500 gallons would be about 25 ppm FC and 23 ppm CYA (so yes, you were right).

Did you use the FAS-DPD chlorine test in the TF-100? If so, did you see a "flash of pink" when you added the DPD powder? Add another scoop or two if you saw some pink since the additional powder should have the color hold at which point you can do the rest of the test counting the drops. Since you expect the chlorine level to be high, you could use a 5 ml sample size and count each drop as 1 ppm if you want (or just use the 10 ml sample size where 25 ppm FC would be 50 drops of FAS reagent if the chlorine held that high).

If you have the TF-100, then you can also use the OTO chlorine test that comes with it since that doesn't bleach out. That will tell you if the chlorine is really zero or just very high.

Let us know the result. Also, let us know if you have an ozonator for the spa.

If your chlorine reading is truly zero, then your weeks with no sanitation may have led to some serious biofilm formation in which case a decontamination will be needed, starting with Spa System Flush and then superchlorination and then draining anrd refilling again (unfortunately). In a spa without an ozonator, the daily chlorine loss with no bather load should be around 25% when the water is fairly fresh.
 
I just tested the water using a 5 ml sample size and my FC reading is 11. This reading comes 6 hours after I added the 2 oz of dichlor, so assuming that did bring the FC up to 25, I've lost more than half of that in 6 hours.


The hot tub does have an ozonator....so this means I'll be using more chlorine?

Should I just assume that I have some degree of biofilm in my hot tub and go ahead and start the process of decontamination?

The previous owner told me he recently performed a spa clean, but I'm not sure exactly what he did.

Is there a specific link you could point me to that details the process?


Any spa store would have a spa system flush for me to get started on this today, right?


Thanks for all your help...
 
You only need to start out your soak with a small amount of chlorine, 1-2 ppm FC is what most users do, since that minimizes chlorine smell during the soak. If you're soaking with strangers and want to have faster prevention of person-to-person transmission of disease, then you'd want more like 4 ppm FC so that it lasts through the soak.

Unfortunately I can't tell whether your spa is using so much chlorine because you have an exceptionally powerful ozonator or whether you've got biofilm growth, probably in the piping though I'm betting it's more likely the latter. You can use your spa and just add more chlorine (I'd use more Dichlor until you get the CYA up to over 30 ppm and then switch to bleach) making sure you add enough to measure at least some FC before your next soak. If you find the chlorine demand staying high, then you can do a decontamination to see if that gets rid of it. You might also see if there is some way to have your ozonator not run as frequently.

See Using Chlorine in a Spa and for decontamination see this post.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Chlorine demand seems to have stabilized...

at 7:00 pm I had FC 8.

At 9:15pm: FC 7


I think I'll test it again around midnight, and if it stays around 6 or 7, should I add more dichlor, or wait until the morning to test again?

Related question: I currently have my filtration cycle set at 6 hours, twice a day. How long should I have filtration cycle duration for? 2 hours? 4? 6?
 
6 hours twice a day is 12 hours which is too high for a hot tub which has relatively short turnovers (usually around 20 minutes) given the small water volume. Why don't you try cutting that in half and split it up to three 2-hour circulation cycles for 24 hours so one cycle every 8 hours or something like that (if you can). I'll bet the ozonator runs when the circulation is set to run so cutting that in half may cut the chlorine demand way down.

I think you can wait until morning to test again. If cutting back the circulation time cuts down the chlorine demand then you probably don't have to decontaminate. If you do end up having to decontaminate, use Spa System Flush as the first part of the procedure before you superchlorinate.
 
You just need the circulation pump running. No need to run the jets unless your circulation isn't good for some reason. If it's easier for you to control turning on/off the jets, you can add the chemicals with them running but be careful not to add chemical so that it will splash back out at you (wear glasses or goggles if you're not sure it's safe).
 
You must log in or register to reply here.
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.
Top Bottom
Back
Jump to latest Follow Reply