[Nitro's Approach To Water Maintaince]

FlowerChild, I was just reading "What's The Step By Step To Bromine Treatment?", and in there waterbear said:

"If pH is not between 7.2 and 8.0 then you should adjust it before entering the spa and wait abot 30 minutes then retest it to make sure it is in the proper range."

So I'd say 30 minutes.

[Help, need advice in water maintenance]

I'm guessing your water is unsafe. "Andrew Thomas Weil is an American celebrity doctor who advocates for alternative medicine." (wikipedia, citing 6 non-celebrity sources). Personally I'd be very interested in all of his recommendations, as products to avoid.

As for solutions, the "chlorine smell" is chloramines, which are normal and produced when chlorine is getting spent sanitizing grime, but well-maintained water usually doesn't produce offensive amounts of chloramines. I'd recommend reading Dichlor/bleach Method In A Nutshell for chlorine sanitization, or What's The Step By Step To Bromine Treatment? for bromine sanitization.

[Filter Cleaner]

I use Leisure Time Filter Clean, and the warning label says "Danger: contains sulferic and hydrochloric acid". So if I were going to buy something in bulk to water-down and clean filters, I'd probably start with muriatic acid from the hardware store.

Searching google for "clean spa filter muriatic acid" shows that other people have tried this, but I haven't read into whether or not it's a good idea 😅

[Calcium Increaser effect on PH]

I am a fairly new hot tub owner (this is my 6th month owning a hot tub) so I'm learning a ton lately, but am also still wrapping my head around many concepts. I did find a couple relevant posts from a couple threads.

First is a post from this thread where a question very similar to yours was asked near the end:

On 6/16/2010 at 1:27 PM, chem geek said:

Calcium Hardness (CH) does not affect the Total Alkalinity (TA) nor the pH. However, together, along with temperature (and TDS), they affect the saturation index, but for spas that's only a problem if these parameters are high as that can cause scaling. You can use The Pool Calculator to calculate the saturation index -- so long as its at least a little negative, you shouldn't get scaling.

And second is this thread where a correlation between rising-pH and TA is made:

On 2/24/2012 at 1:21 AM, chem geek said:

Your pH keeps rising because your Total Alkalinity (TA) is probably too high. TA is a SOURCE of rising pH. Yes, everyone talks about it being a pH buffer to stabilize pH, but the carbonates part of TA (which is almost all of TA if there are no borates or CYA in the water) makes the pH rise, especially when there is aeration of the water, because carbon dioxide outgasses from the spa. It's just like a carbonated beverage. If you are adding acid, then that would normally lower the TA so the only way the TA is staying high is that you are raising it (or perhaps it started out very high from the initial fill water) -- so stop doing raising the TA and let it get as low as 50 ppm if necessary. You could use 50 ppm Borates as well, after you get your TA lower.

So maybe for some reason an ALK of 85 in your case is too high? Or since you're preparing a new fill of water there's been more aeration than usual?

[Wondering why TA and CH dropped suddenly]

I've thought about this a little more, and have a theory. Leisure Time "pH Balance" also says "pH Balance will soften hard water and precipitate calcium, resulting in cloudy water and/or a clogged filter". I have noticed evaporating water is starting to leave scale behind, so trying to increase CH when using "pH Balance" is a bad idea.

I found this post explaining how "pH Balance" is a phosphate buffer, how CH helps reduce foaming, how CH helps protect plaster/grout, and otherwise serves no purpose. Then I also found this post which explains how increasing CH is a bad idea when also using a phosphate buffer.

I think the solution to my problem is simply realizing I don't really have a problem: treatment and usage are going to affect pH, adequate TA will allow pH to remain level for a while, and CH doesn't matter since I have an acrylic shell hot tub (no plaster, no grout, etc). I also somehow got it in my head that keeping LSI between -0.3 and +0.5 would make the water more inviting because everything was balanced, but re-reading that part of my "Pool & Spa Water Chemistry" manual that came with the K-2106 reveals that's not true: a balanced LSI is for preventing scale or damaging concrete/metal.

So to resolve my minor scale issue I'm going to replace some treated-water with hose-water every now and then until scaling stops, and not care about my CH until this phosphate-buffered water gets replaced in a couple months. Also I probably won't use "pH Balance" any more, in favor of relying on a proper TA to prevent pH drift between checks/adjustments.

I hope I haven't introduced any misinformation, someone definitely correct me if that's the case because I've owned a hot tub for a total of about 5 months now 

[Wondering why TA and CH dropped suddenly]

Hello, I'm a fairly new hot-tub owner, and have found tons of valuable resources on this forum. Now that I have a slightly complicated question, this was quickly my first-choice to seek guidance  My tub is 425 gallons (Alps Spas Q-90), last cleaned and refilled on 1/22/17 (sodium bromide + floater + MPS), consistently tested with a Taylor K-2106 kit, and set to 102F.

Problem is my measurements today have me really scratching my head. TA dropped, and my CH plummeted. I've been busy so the tub's only seeing 1 or 2 bather-hours a week lately. Here's the last few measurement entries in my logbook:

2/11/17: pH=7.3, TA=120, CH=100, SI=-0.3, TB=0.5
2/12/17: pH=7.6, TA=130, CH=100, SI=0.1, TB=5
2/16/17: pH=7.6, TA=130, CH=90, SI=0.1, TB=4.5
2/20/17: pH=7.4, TA=90, CH=40, SI=-0.7, TB=5

Should I be worried that CH and TA tanked? I know bromine is acidic, which can lower pH and TA over time, but I've never seen my calcium dive like that.

Also, I did add Leisure Time "pH Balance" during this last refill, which says "Note: due to the unique buffering capacity of Leisure Time pH Balance, it is not necessary to adjust the calcium hardness level in your spa". Was that a mistake? Could it be interfering somehow?

Thanks in advance!