Hot Tub Water Balance
Recently I received a private message on our Facebook page. It was requested that I write about hot tub water balance specifically pertaining to our Minnesota water source conditions.
Most wells in our trade area carry an amount of Iron. Even city water sources have Iron in their water. So as I address chemical balance, I will keep bringing up the reminder of removing the Iron from the water.
So the exact question was “Please explain the importance of water balance and why my spa is easier to maintain now versus when it was new?”
The answer to your question can be responded to a few ways - I will first give
you the answer that has worked for our customers in the northern MN water source scenarios.
"The first batch of hot tub water is always the hardest to maintain, reasons
being it's a new hot tub (factory water test film on plumbing, shells?), for a
lot of people it's their first hot tub and balancing chemicals is new to them,
the user (soaker) load is very high when the product is new and a lot more
consistent vs. a ways down the road it reverts into a normal routine (less use,
easier to control)."
With that said, typically our customers primarily only concern themselves with
PH balance, as that has the most effect on our skin and spa equipment - Most of
our customers drain their spas every 3 to 4 months so realistically long term TA
balance should not be a issue due to the short time frame of the water contained
in your hot tub.
Also, I only encourage you to test your PH and adjust once a week if at all.
You would not want to test everyday, as that is too quick and the water likely
has not adjusted to the previous test, so just once a week. Importantly, when
lowering your PH, do so by pre-dissolving the PH DECREASER in a ice cream style
bucket, simply dip the bucket in the hot tub water, add your PH DECREASER to the
water and mix it to a liquid solution. Add it to the spa, run the the jets for
15 minutes and check again - repeat this process 3 or 4 times to obtain PH
Neutral (7.2 to 7.6)
I have seen and tested the products being promoted as "Perfect PH" and "PH Lock"
- they are to me over promising success at a cost that does not meet my cost of
ownership goals for our customers. Also, there is far too many variables for
them to succeed.
With all that said above, here is some industry guidelines:
PH is low, but TA is high (likely old water that should be changed): Add Ph
decrease to lower TA, then add PH increase to raise PH. (I recommend a water change)
PH and TA are both low: Add PH Increaser
PH and TA are both high: Add PH Decrease every 15 minutes pre dissolved, likely
will take 3-5 15 minute intervals.
PH is normal, but TA is high: Add PH Decrease to lower TA, if PH drops below 7,
add PH Increase slowly to raise.
PH is high, but TA is normal: Add PH Decrease to lower PH, if TA drops below
normal add Alkalinity Increaser to bring it back up
PH is high, but TA is low: Add PH decrease to lower PH. Then add alkalinity
increaser to bring TA back into range, it will not raise PH above normal range.
PH fluctuates wildly: This is usually caused by low TA. Bring TA up into line
With Alkalinity Increaser
as needed, and make
final adjustments to pH if necessary. Likely if it is newer water, you are
testing too much, give it time - if it is older water a water change is advised.
High Iron in your source water may add some steps in obtaining quality water. I
recommend always using a "turbo ion exchange pre-filter" when filling any unit
with water in Minnesota. It's a $40 filtration system that I allow to be sold
at cost in the stores and online I believe in it so much, $19.99 -
High Iron for a spa can easily be removed by remembering these steps:
1) Use the Turbo Ion Pre Filter when filling
2) Always add 1/2 bottle of METAL CONTROL when filling the spa
3) At approx. 80 degrees, remove and rinse your filter (s). The Metal Controls
job is to "bond" any iron that made it's way thru the ION PRE FILTER. By
bonding the iron, it then gets trapped in the filter, but it's the operators job
(you :-)) to remove the filter and rinse the bonded iron away.
4)At this point, in a high iron environment (your filters were really coated in
iron) add the second half of the metal control and wait another two or three
days before adding any sanitizer (chlorine or brilliance)
5)Sanitizer (chlorine or brilliance) reacts with Iron in your heated spa water -
and it may cause the water to go from clear to green or tinted.
6)Regardless of iron / chlorine levels, once your water is heated to 80 - you
can adjust the PH level -
*pH is low, but TA is high* Add pH Decrease
*pH and TA are both very low* AddpH Increase
*pH and TA are both high* Add pH Decrease
*pH or TA are stubbornly high* Add pH Decrease every 15 minutes
*pH is normal, but TA is high* Add pH Decrease, then add PH increase to raise pH
*pH is normal, but TA is low* Add Alkalinity Increaser
*pH is high, but TA is normal* Add pH Decrease
*pH is high, but TA is low* Add pH Decrease
*pH fluctuates wildly* This is usually caused by low TA. Bring TA up into line
with Alkalinity Increaser
as needed, and make
final adjustments to pH if necessary per this guide table.
*pH drops after adding non-chlorine shock* Prevent this by adding about 3/4
Teaspoon Alkalinity Increaser
*Bad source water or well water makes balancing difficult* Reduce contaminants
by using a hose-end water pre filter as mentioned above.
Some tricks my family uses in our own personal hot tub may help you – We generally try not to dunk our heads under the water as the shampoos and products will have an effect on the water balance and clarity. Sometimes we don’t care and have fun, but just know that you may have foaming and other issues from doing this. Swim suits are a big factor as well. In theory, we dry our suits in the dryer or hang them, we try to keep them from the washing machine. The soaps carry thru to the hot tub water and rinse out at your hot tub and can cause the foaming and pH bounce.
I hope this helps! Feel free to submit a question on our contact form below and I will happily give you our answer / opinion on the subject!
Hot Tub Phil