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Chemical Balance of Hot tub, specifically Chlorine

Chemical Balance of Hot tub, specifically Chlorine


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Old 05-10-19, 05:26 AM
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Question Chemical Balance of Hot tub, specifically Chlorine

Good morning,

I just read the sticky on chemistry and it has a lot of good info in it. I just want to clarify a couple things.

I just fired up my tub for the first time and have some chemistry questions. I failed chemistry in school so I am by no means a water chemist. However, I'm really good at following directions and finding the correct information and am having a little trouble finding a clear answer for my specific question. Details below.

I received a couple items with the purchase of my new Hot Springs spa. I received the inline cartridges for the Frog system. I also received a startup kit for pro team spa. Talking to my dealer, they instructed me to follow the instructions for startup on the Pro team spa package, and then start the Frog system. So that's what I did, up until the Frog.

I figured I'll want to get this down and understand it fully since I'll be doing this every 3 or 4 months with a water change. Here's the steps I took.

Added Gentle Spa and let jets run for 20 minutes. According to description, Gentle Spa improves water condition and adds fragrance and moisturizers.

Then I added Metal Magic which is supposed to remove iron, copper, silver, and excessive hardness. I let jets run for 20 minutes before moving on.

The next couple steps is where I'm confused.

I added a sanitizer as instructed(Di-Chlor) to my tub and waited 30 minutes. After that, it instructs me to shock the water using Multi Magic. A quick google search told me that Multi Magic is their shock treatment, but my bottle says oxidizing shock, so I added that as instructed and waited 20 minutes.

After all this and before starting frog, I wanted to check my chemistry, so using a test strip, I found that my hardness, alkalinity, and ph were all good, although on the high side. My total chlorine was showing 10+ ppm and my free chlorine was showing 20+ppm.

Does it sound correct that I added chlorine then right after that, shocked it? The bottle for the oxidizing shock says it's a non-chlorine shock, but I was certain that the Di-chlor I added was the correct amount. Should my chlorine numbers have jumped so high? How long does it take for those numbers to come down to a safe level?

Once they're at a safe level, I'm assuming that I can put the frog system in and that will maintain my chlorine levels? Thanks in advance for the help!

Short Side-bar: While the color strips are easy, I'm more of an exact number type of person. Are there any good digital testers for hottubs/pools that someone could recommend? I've seen a couple on Amazon but it looks like they get bad reviews and the readings are not consistent.
 

Last edited by bjlasota; 05-10-19 at 05:29 AM. Reason: Add information
  #2  
Old 06-17-19, 02:20 PM
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You are being taken in by the spa chemical industry. You do not need all that chemicals. Check out GREEN Spa and Hot tub chemicals or look up the book Love Your Spa/Hot tub again on Kindle.
 
  #3  
Old 06-17-19, 04:35 PM
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Having owned a swim spa's and hot tubs for about 20 years one thing you will eventually discover is that all that crap they sell does one thing, drain your wallet.

There are only 3 things you need, chlorine (liquid or tablets) muriatic acid, and baking soda. All very cheap and plentiful items.

A good tester, I use Aquacheck and some experimentation to find what amounts of chemicals drive what levels of water change!

Test the water, find out where your at, ad an ounce or two, check the next day and keep going till it's close, does not have to be the absolute neutral value.

Same goes for filters, buy their recommended multi layered filters and your out $30 each, I found a cheap $8 replacement filter that when it's trashed I have no issue throwing into the fire pit!
 
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Old 06-17-19, 04:47 PM
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Holly cow! I have never heard of such chemical usage. I've had Hot Spring spas for 30 years and have never used so many products. I assume your spa has ozone injection so that is always working to help sanitize.

When I fill my spa I put the Nature2/Spa Frog into the filter tube and turn on the spa. I give it a good shock with either MPS or dichlor clorine with the main jets running for 10 minutes. Then I test for pH and hardness and add chemicals as needed. Wait for the water to heat and enjoy.
 
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Old 08-08-19, 10:02 AM
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Issues upon refill

I wanted to re-open this thread because I have a few new questions.

I was able to simplify balancing my water on my initial startup without adding all the junk and had a successful 2 months of running without issue and water perfectly balanced.

Just recently, I drained and cleaned the tub, refilled, and am attempting to get the spa back into balance from this latest fill and for whatever reason, I can't get it right. Below are my steps, then the issue.

1. Refill water to 1" below seat pads.
2. Re-install filter
3. Purge pumps.
4. Let warm up to 90 Degrees
5. Adjust PH and Alk as necessary. I use PH + and PH- by Pro Team Spa to set these values.
6. Check hardness(I use an RV filter to fill the spa, so my hardness is usually on point the last 2 fills).
7. Super Chlorinate with 1.38 TBSP of Dichlor by Pro Team Spa
8. Once my FC has dropped back down between 1 and 3, I'll insert my Frog Mineral and Chlorine cartridges on their proper settings.

If that looks good, onto Issue.

I set the hardness and alkalinity and can normaly get those in check. Ph is another story. Upon initial check, pH strip shows it's way over 8, so I use pH- to bring it down. I've gotten it down to around 7.2 and let sit overnight, and it acts as though the pH rises over a 24 hour period. On one occasion, I got the pH down to 7.2 then introduced my chlorine and within 12 hours, my total chlorine reads 5-6, my free chlorine reads 0, and my pH appears to be skyrocketted again over 8.

I've tried multiple brands of strips to make sure one wasn't bad. Last week over the course of a few days, it looked like my pH was set and would stay around 7.2, so I introduced a superchlorinate and then the Frog system and let sit for a couple days. Checked the water and again, the TC was around 5-6 and the FC was 0, and the pH was around 8.0+.

I took a water sample to my local spa shop and they basically said, Yup, your PH is high, try this, and offered me a pH- bottle which I politely declined since that's basically what I've been using to try and get my pH in check. Like I said, I've used color strips, the Aquachek digital scale, and even the frog color scale that came with my frog cartridges. The Aquachek gives me a digital value of 8.4 and says hi, Chlorine 0, and Alk is around 120.

The kid at the spa shop did not seem interested in helping me so I don't plan to go back. What am I missing, doing wrong, or both?
 
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Old 08-08-19, 11:49 AM
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What is your total alkalinity after adjusting your pH? It may have fallen which will make holding a stable pH more difficult.
 
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Old 08-08-19, 01:07 PM
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When I lower the pH down to 7.2, the Alk does drop, but not below 80. I believe it's somewhere around 100 after using pH down. I know that pH and Alk have to be spot on or at least within range and stable for your chlorine numbers to work. I've also heard pH will climb a little when you introduce chlorine after you're balanced. What I can't explain, is why my pH climbs overnight without adding anything else. The bottle for the pH+ and - I'm using say to wait 15 minutes before re-checking, but I normally wait 1-2 hours before re-checking and adjusting as required.
 
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Old 08-08-19, 05:18 PM
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As mentioned, there are only 3 things you need, chlorine (liquid or tablets) muriatic acid, and baking soda. All very cheap and plentiful items.

I think your getting too hung up on the numbers, check the water, add some chemicals, wait 24 hours recheck, add some chemicals.

Eventually you will get there, if your checking shortly after adding chemicals you may be causing issues by not allowing everything to stabilize, thus chasing a moving target!
 
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Old 08-09-19, 04:59 AM
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Have you checked your water's hardness?

I don't have much recent experience with chlorine since I've used MPS for the past 15 years and only shock occasionally with chlorine. I don't know why chlorine raising your pH. Reading online I see that chlorine is acidic so I would expect it to lower your pH. I did read that excessive chlorine can make pH and alkalinity tests inaccurate. The only other thing I can think of is if your bubbles are turned on. Running the jets with the air turned on will raise your pH surprisingly quick.

I do know that after my last fill I had to add a few times to get my alkalinity up in the desired range. If I tested immediately after adding alkalinity increaser (yes, I know you should wait 6+ hours before testing) it would show that it was in the proper range but when I tested the next day it would be low again. After 3 or 4 additions of increaser the alkalinity finally stayed in the proper range. After that my pH only slowly moves, largely based on how much the air jets are used.
 
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Old 08-09-19, 05:36 AM
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Thank you for the insight. I did read about the bubbles increasing the ph and forgot to turn those off.

I took my samples to another location and they did a phosphate check and my phosphates are sky high. They told me that phosphates will eat up your chlorine. So I'm thinking my issue is that I have my air jets on and high phosphates are giving the false high pH reading and 0 chlorine. I worked on re-balancing the water last night, turned the jets off, balanced the chlorine levels, and dumped in some phosfree that's a natural product that will get rid of the phosphates or at least lower them. I have a phosphate test kit on the way and should be here tomorrow. I'll spend some time this weekend keeping an eye on balance and try to get my numbers in check.

After I can work with these store bought chemicals and keep my water in balance, I may switch over to the muriatic acid method or even the hydrogen peroxide method. But for now, with the chemicals I have, I enjoyed my spa for 2-3 months when I was able to keep everything in check.
 
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Old 08-09-19, 09:45 AM
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My home is on a well and the water is quite hard and was always difficult to manage and required more chemical additions than I wanted. So, for each fill I bring home water from the city. This has made water maintenance MUCH easier. I have a 330 gallon IBC liquid shipping tote that I put in the back of my truck to carry the water. You might be able to find a water hauling company or someone with a tank that you could hire if you want to go that route.
 
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Old 08-09-19, 10:05 AM
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I have city water and live in the city, so my water is pretty much spot on out of the faucet. It's tweeking that pH and Alk just enough to get it in the acceptable range. I'm going to take a look at it tonight without the aeration. I will balance out my pH and Alk with all my aeration off and see how that works. I dumped the phosfree in last night and am letting it run last night and during the workday today. I'll be able to check my phosphates tomorrow when my test gets delivered. For tonight though, I'm going to shut all the aeration off and check my numbers. My hardness out of the faucet is somewhere between 250 and 500.
 
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Old 08-09-19, 02:27 PM
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my phosphates are sky high
Ahh, I think your being taken again, I have never, ever, heard of phosphates being a component of pool/water chemistry.

Phosphates are a component of fertilizer, if you phosphates are "sky high" then they are coming from your water source which is your city water!

If true, your issues go way beyond the spa, you are drinking phosphate contaminated water!
 
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Old 08-10-19, 04:20 AM
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Some municipalities add phosphate to their water as a corrosion inhibitor. It helps prevent lead and copper leaching from pipes.
 
 

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