Drained Hot Tub

[nirvleach]

Good afternoon...

I'd first like to thank TFP for helping me with my pool summer. I don't post a lot but I have been reading and learning a ton about how pool chemistry works and I have had a very successful summer with my pool...

I bought my house in June and it came with a pool and a hot tub. The previous owner told me that it was time to drain the hot tub because it should be done every 6 months or so... Knowing that I was going to have my hands full with the pool, I decided to drain the hot tub and keep it empty until it was time to close the pool.

Well now that it's getting colder I decided to start the process to get the hot tub up and running. It's been empty and not running (I flipped the circuit breaker off) for about 3 months. Occasionally I would lift the cover to check to make sure nothing was growing inside the tub and everything looks fine.

The hot tub is a Master Spa LSX http://www.masterspas.com/lsx.php

The previous owner left me a bunch of chemicals which are all "Leasure Time" Spa chemicals and are listed below:
- Spa 56 Chlorinating Granules - http://www.amazon.com/Leisure-22337-Chl ... B000NCW904
- RENU2 Renew Non-Chorine Shock (About 10 bottles of this) - http://www.amazon.com/Leisure-RENU2-Ren ... 000LS2HEI/
- Spa Defender - http://www.amazon.com/Leisure-Time-Spa- ... 000NJ7JRK/
- Jet Clean - http://www.amazon.com/Leisure-Time-4545 ... 000NCOC6I/
- Bright and Clear - http://www.amazon.com/Leisure-Time-Brig ... B000NJBA5C
- Metal Gon - http://www.amazon.com/Leisure-Time-Spa- ... B000V87OY6
- Spa Down - http://www.amazon.com/Leisure-Time-2233 ... B000V8BUBE
- Foam Down - http://www.amazon.com/Leisure-Time-HQ-F ... B000PSBAS8
- Plus some spa fragrances

Here are my questions:

1) Should I decontaminate http://www.poolspaforum.com/forum/index ... tamination the tub? The water did not look bad when I drained it but it's been sitting empty. I guess it couldn't hurt to do it, but if I don't need to, I'd like to skip it. What should I look for to decide if i should decontaminate or not?

2) I plan on using the Dichlor/Bleach method. I assume i'll use the Spa 56 Chlorinating Granules to get CYA to 30ppm then use bleach the rest of the way. Is this correct? Is 30ppm CYA too much? My spa will get no sunlight, it has a cover and is under a roof. It also looks like my spa has an ozonator. Will that affect my target CYA?

3) Once everything is balanced, what would I use the Renew Non-chlorine shock for mentioned above? They seemed to have left me a lot of this and I'm not sure where it would fit in with the Dichlor/Bleach method if at all. Would I be able to use the other chemicals at all using this method also?

Thanks again for everyone's help.

Oh and FYI I have the TF-100 test kit.

 

[YippeeSkippy]

I'm not positive (never having done it) but I think the decontamination process is on a tub full of water which you'd have to then drain out again.
How was the water looking before you drained it 3 months ago and had you ever tested it for CL and CC? I tend to drain mine every 3-4 months, even though it gets light usage. I keep a few of the cleanable filters around to quickly swap them out when I empty and clean my spa.

 

[nirvleach]

I'm not positive (never having done it) but I think the decontamination process is on a tub full of water which you'd have to then drain out again.

Right, which is why i'd like to skip the decontamination process so I don't have to fill then drain again...

How was the water looking before you drained it 3 months ago and had you ever tested it for CL and CC? I tend to drain mine every 3-4 months, even though it gets light usage. I keep a few of the cleanable filters around to quickly swap them out when I empty and clean my spa.

I didn't test the water in the spa water at all. I guess looking back I should have, but the water looked fine to me. I was left with spare filters. They are clean and I plan on using them when I fill the spa back up.

 

[linen]

Draining a hut tub but not blowing the plumbing lines out is a common cause of biofilm growth inside the plumbing. With that said, you could take a chance and not do the decontamination step and see what the FC consumption per day is on yours. If it is higher than 25%/day (assuming hot tub temps and no ozonator), then you likely need to decontaminate.

 

[YippeeSkippy]

Draining a hut tub but not blowing the plumbing lines out is a common cause of biofilm growth inside the plumbing. With that said, you could take a chance and not do the decontamination step and see what the FC consumption per day is on yours. If it is higher than 25%/day (assuming hot tub temps and no ozonator), then you likely need to decontaminate.

I don't know how to "blow out the plumbing" actually. Can you 'splain Lucy???

 

[chem geek]

1) Should I decontaminate http://www.poolspaforum.com/forum/index ... tamination the tub? The water did not look bad when I drained it but it's been sitting empty. I guess it couldn't hurt to do it, but if I don't need to, I'd like to skip it. What should I look for to decide if i should decontaminate or not?

2) I plan on using the Dichlor/Bleach method. I assume i'll use the Spa 56 Chlorinating Granules to get CYA to 30ppm then use bleach the rest of the way. Is this correct? Is 30ppm CYA too much? My spa will get no sunlight, it has a cover and is under a roof. It also looks like my spa has an ozonator. Will that affect my target CYA?

3) Once everything is balanced, what would I use the Renew Non-chlorine shock for mentioned above? They seemed to have left me a lot of this and I'm not sure where it would fit in with the Dichlor/Bleach method if at all. Would I be able to use the other chemicals at all using this method also?

The "blowing out the lines" means drying them out and removing water by blowing air through them. That would be something the manufacturer or dealer could do. For you, it would be about decontaminating to remove biofilm, but you could see how things go and deal with that only if needed.

If you do have an ozonator and if it is powerful or on a lot of the time, then it will decrease the amount of chlorine needed to handle bather load but will increase the amount of chlorine needed in between soaks if the spa is not used. That means that the ozonator is helpful if you plan to soak every day or two, but if you only plan to soak once or twice a week, then the Dichlor-then-bleach method (or any manually-dosed chlorine method) will be more work since you will need to dose the spa every day or two.

A target CYA of 30-40 ppm is appropriate and for your spa has nothing to do with sun exposure. It has to do with moderating chlorine's strength.

The non-chlorine shock would not be useful with the Dichlor-then-bleach method. It is not a disinfectant. It would be useful if you were using the Nature² system that uses silver ions, but you aren't.