Adjusting chemistry of new hot tub -- and question about stain line at water level line

[HTUB]

Hi everyone,

First of all, thanks for providing all of this useful information. It's incredibly helpful. We recently purchased a Hot Spring Envoy. The pool store folks set up up for us a month ago and recommended only to use dichlor, which I assume is common. However, the more and the more I've read I'm so confused about why all pool stores do this since the CYA will climb sky high in just a couple weeks, and the hot tubs just won't be sanitized based on the FC/CYA ratios.

I have a TF-100 test kit, and last week I checked the CYA and it was above 100. So, I drained the tub and refilled it yesterday to restart. I plan to use the dichlor to bleach method as described here.

I went ahead and added a dose of dichlor to get the FC to 10ppm, and then tested the water. Here are the results:
FC 5.0
CC 0.5
pH 7.5
TA 150
CH 225
CYA 20

I spent yesterday afternoon adjusting the total alkalinity first, aerating and adding dry acid. I went slower just because I was new to this and I was able to get the TA down to 80. My plan is go get it all the way to 50 today.

I have a few questions.
1. Does this sound reasonable? As far as the order of steps? I've read the sticky and many other threads and I can't see any that clearly describe the order to go about things, but it made sense to me to get some sanitizer in there first then control the TA.
2. They gave us a Vanishing Act calcium reducing pillow and put it in when they set up the spa. It did bring that fill of water down to a CH of 100. Water in our area is pretty hard, but a CH in the low 200s seems reasonable to me. Is there any reason to keep using this product on subsequent fills? It's $45 which would mean each fill would be $45+.
3. Is there a consensus on the best place to find balanced borates now? I read that Gentle Spa no longer includes their data sheet so it's unclear the total content now.
4. Finally, I've attached a picture of this weird stain at the water level. There was a more subtle stain after a month of use before draining yesterday. When it drained I wiped off the stain, so this new stain is the result of fresh water and the jets running for a few hours over just one day. I realize now that I probably should have purged the tub first with Ahh-some even though it's new. I have a bottle of this on the way but haven't had a chance to do this yet. Is this stain the result of biofilms from the pipes or from something else maybe?

Thanks again for the help and for this site. I bought the premium version of the app and the calculations and ability to log data and chemical additions is really slick.

 

[Ahhsomeguy]

Hi Htub: What I see does look like a release of bio-gunk. Is it tacky or sticky? Just purge the tub when you receive the product. This should clean out and build-up your plumbing may have. Note: If your Hot Spring has the ceramic filter pleats, do NOT place them in the hot tub proper while purging. You only do this with the pleated monofilament spun-bonded type filters. You must remove the filters while purging.

 

[bradgray]

Hi everyone,

First of all, thanks for providing all of this useful information. It's incredibly helpful. We recently purchased a Hot Spring Envoy. The pool store folks set up up for us a month ago and recommended only to use dichlor, which I assume is common. However, the more and the more I've read I'm so confused about why all pool stores do this since the CYA will climb sky high in just a couple weeks, and the hot tubs just won't be sanitized based on the FC/CYA ratios.

I have a TF-100 test kit, and last week I checked the CYA and it was above 100. So, I drained the tub and refilled it yesterday to restart. I plan to use the dichlor to bleach method as described here.

I went ahead and added a dose of dichlor to get the FC to 10ppm, and then tested the water. Here are the results:
FC 5.0
CC 0.5
pH 7.5
TA 150
CH 225
CYA 20

I spent yesterday afternoon adjusting the total alkalinity first, aerating and adding dry acid. I went slower just because I was new to this and I was able to get the TA down to 80. My plan is go get it all the way to 50 today.

I have a few questions.
1. Does this sound reasonable? As far as the order of steps? I've read the sticky and many other threads and I can't see any that clearly describe the order to go about things, but it made sense to me to get some sanitizer in there first then control the TA.
2. They gave us a Vanishing Act calcium reducing pillow and put it in when they set up the spa. It did bring that fill of water down to a CH of 100. Water in our area is pretty hard, but a CH in the low 200s seems reasonable to me. Is there any reason to keep using this product on subsequent fills? It's $45 which would mean each fill would be $45+.
3. Is there a consensus on the best place to find balanced borates now? I read that Gentle Spa no longer includes their data sheet so it's unclear the total content now.
4. Finally, I've attached a picture of this weird stain at the water level. There was a more subtle stain after a month of use before draining yesterday. When it drained I wiped off the stain, so this new stain is the result of fresh water and the jets running for a few hours over just one day. I realize now that I probably should have purged the tub first with Ahh-some even though it's new. I have a bottle of this on the way but haven't had a chance to do this yet. Is this stain the result of biofilms from the pipes or from something else maybe?

Thanks again for the help and for this site. I bought the premium version of the app and the calculations and ability to log data and chemical additions is really slick.



View attachment 358183

1) My opinion is to not stress too hard about which you do first when it's a spa. Even if you went in perfect order today, you're going to respond to the elements in different orders over the life of that water so ultimately it can't matter too much. Spas are prone to peaks and valleys even with good monitoring because they're so small. Its why most commercial spas are required to have ORP systems by health depts, so that chems can be adjusted *while* the bather is in them. But, yes simply put TA is supposed to be the backbone of your balance, then pH, then sanitizer. But getting some sanitizer in a spa first to ensure the water holds clear while you spend a couple days on the TA isn't going to hurt anything. If you want to use liquid chlorine as your initial dose, that will impact your pH and Alk less than dichlor while you start it up.
2) I'm skeptical of any product additive that claims to reduce hardness. If you think about it, anything less than a physical removal like a home soft-water system is not technically reducing it. Maybe that system is somehow able to do it via the same Ca/Mg swap with sodium method but that would be a breakthrough. I'll do some reading. That said, our water here is 250-300ppm from the tap and we don't stress. If yours is 200, you're within the happy range. Going down to 100 is likely to give you trouble with suds. We find more trouble with low rather than high.
3) Borates are something I'm less familiar with so I won't offer anything here. There are folks who can answer this one better!
4) it could be a number of things, but I'd wager it's just remnants of your prior usage. Oils, lotions, soap etc. As for why its on your walls, low CH but especially surfactants (like swimsuit detergent, deodorant waxes, bodywash etc) are going to "lift" your debris and deposit it at the water edge rather than letting the filter draw it in and capture it like it's supposed to. Remove it with a gentle kitchen sponge that has the green scotchbrite side and rinse the sponge outside of the spa. If it's really waxy, clean your sponge with dish soap. Just be sure to rinse the suds off again before putting back into the spa for round two if needed in a few days.

 

[Methuselah]

I'll add to what @bradgray said --- we bought two packages of fuzz balls that float on the surface and (supposedly) collect oils and the like. When we clean the filter every week or two (sometimes longer) we throw them in the laundry with the whites and use the other set.

I cannot recall if the manual for the hot tub said to do it, or I got the info here, but it is also a good idea to wipe the waterline area with a microfiber towel regularly.

Borites are controversial, some folks use them, others get by just fine without. I think as you continue reading up you will be able to make a somewhat informed decision. If you decide to do it, there's a chemical company that sells a pure granule form. I think it's Duda Diesel?

One of the chemical gurus on this forum recommends dumping the water at no longer than a 2 or 3 month interval, and I think from reading here that many are able to push the interval up to 6 months and that seems to be considered maximum.

On the calcium "pillow", I'd say if you wish to have lower CA, you can attach a filter to your hose for all or part of your next refill instead. My CA was around 100 and when I started to see foaming I pushed it higher to about 140 and on my first refill found it had precipitated in my filter housing. That was probably my fault. You can have CA higher and not have that happen if you have properly balanced water (thank you @proavia). BTW, I didn't get that foaming until about two months after the initial fill, which could have been resolved per the above mentioned suggestion to dump it...

The AhhSome! isn't a bad idea but you mentioned a liquid. I think the one you want is a gel. I let my tub sit for months while we had the slab poured and assembled a gazebo over where we wanted it. Presumably stuff growing it all the while? I purged at the six month mark after finding this site and had hardly any gunk. So either there wasn't much in it, or perhaps bringing the tub to a high shock level a couple times may have allowed the filter to collect the gunk from the plumbing. I found my chlorine demand has decreased after the purge, and I definitely recommend AhhSome!