Confused with Spa

[pooladdict]

Hello All:

I have just put a new spa in our back yard to compliment our inground pool. I am able to use BBB and SWG to keep pool crystal clear through the summer. The Spa, after 2 weeks has become a major P.I.T.A to keep clean, bromine levels appropriate and get rid of foam when using air.

I love the fact that this site informed me on how pool companies misinform people and get them to buy chemicals that are needless in our pools.

I am curious if anyone can help me out with my Spa. I have a Salt System on it, yet I use Brome Add, so I gather that is the bromine, yet, each nite, after use, I am told to drop in Spa Pucks, which are essentially Chlorine Shock?

Is there a way to run my Spa similar to my pool, Chlorine (BLEACH) seems alot easier way to keep it, rather then the hundreds and hundreds of $ that will be spent Spa Cal, Spa Buffer, Bubble Burst, Softener and the list goes on.

Help would be appreciated, I understand that Chlorine wont last as long at higher temps, but there has to be an easier way to run this Spa.

Rik

 

[chem geek]

Using Chlorine in a Spa

Using Bromine in a Spa

Chlorine is less expensive and better in some ways, but it is generally less convenient unless you are using the spa every day or two. This is because with chlorine you have to add it regularly just as you do in your pool so if you aren't using the spa frequently then this can be more work. With bromine, you can use bromine tabs in a floating feeder to keep a background bromine level. Also, with an ozonator, it can also keep a background bromine level. So the choice is up to you, probably depending on your spa usage.

 

[pooladdict]

I have an Eco Clean Salt Water System on my Spa, I guess I am thinking its similar to a SWG?

Would it not be cheaper to drain hot tub every 10 days or so, rather then always adding all the chems my pool company wants me to purchase? My pool water is already balanced, so couldn't I just add liquid bleach to it and basically let it run?

I just find this all to confusing, totally different from our Pool.

This Spa, is being used every nite, 2 people, and easily 6 on the weekends.

I find after two weeks, the water is getting out of control.

Help?

 

[chem geek]

It shouldn't be very different from your pool. The main difference is that with a new spa or an existing one that has never been decontaminated, you may need to go through a superchlorination or use Spa System Flush to get rid of grease, oil and biofilms. Otherwise, your sanitizer/oxidizer demand will be too high. Once that is done, you can maintain the spa easily. For chlorine, you can use Dichlor initially to build up the CYA level and then switch to bleach. Or if you prefer, you can add pure CYA initially and then just use bleach. It is critically important to keep the Total Alkalinity (TA) very low -- as low as 50 ppm or so -- since there is so much more aeration in the spa. The Calcium Hardness (CH) is also kept lower than in a pool -- usually around 120-150 ppm to prevent foaming. Finally, it is strongly recommended to use 50 ppm Borates in the spa as an additional pH buffer (this is most easily obtained from Proteam Gentle Spa since the quantities you need are not large).

Your salt water system may not be able to keep up with your high bather load. It is mostly designed to keep a background level of chlorine between soaks so you will still likely need to add bleach after your soak. You would scale up the amount of bleach based on the number of person-hours of soaking, though with a saltwater chlorine generator the amount will be lower than the normal rule of every person-hour needing 3-1/2 teaspoons of Dichlor or 5 fluid ounces of 6% bleach or 7 teaspoons of non-chlorine shock (43% MPS).

Did you read Using Chlorine in a Spa, especially the summary at the end? I strongly suspect that you are just trying to let the salt system do all the work and you aren't adding enough sanitizer/oxidizer after your soak as a result. After making sure you get the CYA up to around 30 ppm (by either using pure CYA or using Dichlor as your initial chlorine source for some number of days), then use enough bleach after your soak to make sure you end up with 1-2 ppm FC at the start of your next soak.

As for how long you can expect the water to last, assuming you cleaned out your spa at least once (i.e. with Spa System Flush), then with Dichlor-then-bleach (or CYA-then-bleach) you should be able to go twice as long as the standard Water Replacement Interval (WRI) = (1/3) x (Spa Size in U.S. Gallons) / (# of Bathers per day @ 20 min. soaks) where the soak time is presumably 20 minutes or so. You didn't tell me your spa size, but I'll assume 350 gallons with 1-hour soaks and your bather load averages around 3.1 person-hours per day so the tub water with traditional Dichlor-only methods would last around 12 days while using Dichlor-then-bleach (or CYA-then-bleach) you could go at least twice as long or 24 days. Your bather load is quite high, though if your spa is larger than 350 gallons or your soaks are less than 1 hour then the water will last longer than I just calculated.

Though your saltwater chlorine generator will want salt added to the water, probably up to 1500 ppm, what are "all the chems [your] pool company wants [you] to purchase"?

 

[pooladdict]

Hi Richard:

Its not necessarily the amounts, its all the buffers, stain an scale and balancers. I do not use any of that in my pool and it remains crystal clean all year long.

I have gotten the spa back to clear by using more Spa Tabs. The Pool store was kind enough to give me more and inform me that I needed to keep the Bromine up when its being used alot. So I will add 2 or 3 tabs when I have an unusually large amount of usage.

If this doesn't work, I will be switching to Chlorine, I am not now, because the pool store is trying to find out if my system can indeed handle salt water, its currently on Salt Bromide, so maybe the cells are different, I am not sure.

Rik

 

[chem geek]

Yes, with bromine it's the same as chlorine in terms of needing to add enough oxidizer to handle the bather load. More bromine tabs is one way, but you could also just add an oxidizer after your soak -- bleach being the least expensive. The amounts would be roughly what I indicated at the most, but less than that due to your generator and the tabs in the floating feeder.

With bromine, however, you may still need to shock every now and then since bromine doesn't seem to keep the water as clear on its own the way that chlorine can. Some people shock with chlorine; others shock with non-chlorine shock (MPS).