New Hot Tub Owner Slowly Figuring It Out

Hi everyone,

I've already absorbed quite a bit of knowledge from this forum so thank you for that. I have a few questions that are specific to my situation that I was hoping you could help me out with.

I currently have a 1500 L (400 gal for you non canucks) hot tub that is being kept at a temperature of 100 F that was here when I bought a house recently and changed the water right away (about a month ago). The previous owner left behind what he was using which was a trichlor tablets in a floating dispenser and said that's all he did was refill it and shock every once in a while so I just followed his instructions. I know... not good. But after I did a bit of reading, I realized I needed to make a change.

So I took a water test in to my local hardware store (I have a Taylor kit being shipped to me as we speak but this will have to do for now) and I had a pH of 6.8, alkalinity of 19ppm, free chlorine of 14.17 and total chlorine of 16.44 ppm. It also states that the "Stab" level is at 58 ppm (ideal range is stated as 30-60 ppm) so I assume this is the CYA?

After I found this information out, I took the floating dispenser out of the hot tub and bought some 'alk up' product (I know it's the same thing as baking soda) and have now gotten the alkalinity up to 94 ppm and have added a bit more alk up. I have tried opening the hot tub cover and getting the jets going to help burn off some of the chlorine but it's only down to 12.25 free chlorine and 12.25 total chlorine (is it a little weird that they are the same? I guess there's no 'used up' aka combined chlorine in the water?). "Stab" level is at 59 ppm now and pH went up to 8.1 so I have added some 'pH -' product but haven't gotten the water retested yet. I will do that tomorrow morning.

A couple of questions I have:
  1. Would it be safe to use the hot tub right now given my current levels?
  2. After doing a lot of research and scouring this website, I have decided that I would like to use a 3 step bromine system (with MPS for now while I'm figuring things out... I know bleach is preferred due to its price point but bleach % is not easy to figure out based on labels in Canada). I have purchased everything I need (sodium bromide, bromine tabs, MPS) to make the switch. Can I start the switch right now based on my current chlorine levels? In other words, can I start adding my sodium bromide to get my bromine reserve started, shock and add my bromine tabs to the floating dispenser without waiting for the chlorine levels to go down? If the chlorine levels do need to go down, do they need to go all the way down to 0?
  3. As a follow up to the first two questions... If it is safe to go in the hot tub but need to wait for the chlorine levels to go down, then me going into the hot tub would help speed up the use of chlorine right?

Any other tips related to my situation are appreciated too! Thanks for the help.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
10,486
Northern NJ
Yes, with CYA 60 a FC level of 13 is safe to be in. Use the [FC/CYA][/FC/CYA] to determine safe levels of CL. A FC level up to shock level for your CYA is safe.

Being in the spa will not make a difference in CL use.

I leave it to others to comment on your transition to bromine.
 

jza1736

Silver Supporter
Apr 21, 2017
536
Greenlawn, NY
I have a bromine spa. I think it's very easy to maintain and the bromine is more effective at the higher Temps of a spa. IMO, I would wait till your next drain and fill to do the switch. Also, I would do an ahh-some treatment at your next drain and fill.
 
I have a bromine spa. I think it's very easy to maintain and the bromine is more effective at the higher Temps of a spa. IMO, I would wait till your next drain and fill to do the switch. Also, I would do an ahh-some treatment at your next drain and fill.
Thanks for the response. I ended up making the switch to bromine but I will definitely look into the ahh-some treatment next time I drain.

As an update... after I balanced the pH/alkalinity levels a bit and the chlorine level went down below 4 ppm, I added the sodium bromide, shocked it with MPS and then added the floating bromine tablet dispenser (just barely opened). 1 hour after I did this, I went to Home Hardware for another test and these are the numbers I got for a bromine spa:
- pH = 8.5
- alkalinity = 66 ppm
- calcium hardness = 145 ppm
- bromine = 27.36 ppm

So I had a big jump in pH (up from 7.5 pH beforehand), alkalinity went down a little bit (from the 70 ppm beforehand) and bromine levels are very high. Is this normal right after starting a bromine spa?

Today (2 days later), I got another test from Home Hardware after just letting the hot tub be and not adding anything to it:
- pH = 8.4
- alkalinity = 66 ppm
- calcium hardness = 145 ppm
- bromine = 14.7 ppm

Should I continue to let the bromine levels drop before trying to correct alkalinity/pH? Also, is this tub currently fine to use given the current levels?

Thanks again for the help!

- - - Updated - - -

Yes, with CYA 60 a FC level of 13 is safe to be in. Use the [FC/CYA][/FC/CYA] to determine safe levels of CL. A FC level up to shock level for your CYA is safe.

Being in the spa will not make a difference in CL use.

I leave it to others to comment on your transition to bromine.
Thanks for the info! :)

- - - Updated - - -

If you have not done a drain and refill, this would be a good time, you may also want to do an Ahh-some treatment, then startup fresh with the Bromine....
I'm not a patient man unfortunately so I made the switch to Bromine! :confused: Hopefully I can get the water chemistry right now.
 

jza1736

Silver Supporter
Apr 21, 2017
536
Greenlawn, NY
You can remove the cover where your electronics are. It should have a wiring diagram. Look if it says Ozone generator.

Look at the components inside the tub. See if any say Ozone generator.

Or just shoot for 4. It's in range either way. [emoji846]
 
You can remove the cover where your electronics are. It should have a wiring diagram. Look if it says Ozone generator.

Look at the components inside the tub. See if any say Ozone generator.

Or just shoot for 4. It's in range either way. [emoji846]
I took a look and I don't see anything that says 'ozone generator' but I did see a label that says 'ozone' on a white sticker just above a couple of other white stickers that say 'pump' and 'light'. All of the stickers have an arrow pointing towards the hot tub.

If this is an ozone generator, is there a way to know if it's actually working (e.g. turn it on/off) and is there anything you have to do to maintain it?

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santacruzpool

Gold Supporter
Feb 24, 2015
688
Santa Cruz, CA
You need to see if anything is plugged into the connector that the Ozone label points to. My control pack has a few extra connectors - one of them is marked as ozone like yours is - since I don't have an ozone generator that connector has nothing plugged into it.

My control also has a arrow and label for light, and pump - and there is a cord plugged into each of those locations.

If something is plugged in where your label says ozone, then just follow that wire to a little box/pack device and that should be the ozone generator - you could take a picture of that and post it if you are unsure...
 
You need to see if anything is plugged into the connector that the Ozone label points to. My control pack has a few extra connectors - one of them is marked as ozone like yours is - since I don't have an ozone generator that connector has nothing plugged into it.

My control also has a arrow and label for light, and pump - and there is a cord plugged into each of those locations.

If something is plugged in where your label says ozone, then just follow that wire to a little box/pack device and that should be the ozone generator - you could take a picture of that and post it if you are unsure...
Just checked it out and I guess I don't have an ozone generator since there is nothing plugged into that spot and there is something plugged in where it says light and pump. Thanks for helping clarify that.