Understanding Water Chemistry
so you bought a spa to relax, reduce stress, relieve tension and to get
away from the fast-paced world around you. You've used it a couple times,
and have found that it really is all those things and more. As a matter
of fact, you don't know how you lived without it. It's great! But it is
on this occasion when you lift the cover to get in, that it is no longer
the sparkling clear water you are used to, but a cloudy and smelly mess.
The pump and filter seem to be working, the water is warm, and except for
the way it looks and smells, everything seems to be OK. You find the owners
manual and notice it recommends that you test your water. You see words
and numbers like PPM (parts per million), sanitizers, total alkalinity,
pH, and something about the possibility of the water being hard. This stuff
would scare anybody. You panic! You don't know what to do.
So, you get the picture. Although this is a typical scenario, water chemistry
doesn't have to be scary or difficult to understand.
The first thing that you need know is that your spa is not a tiny pool.
Spa water - its treatment and parameters - is much different than a swimming
pool . The main difference of course, is the temperature - spa water is
most often set between 102 and 104 degrees Fahrenheit, while a pool stands
typically at 82 degrees, which also means that there's far more opportunity
for bacteria growth in a spa. Plus hot water opens pores, making bathers
much more susceptible to skin infections. When not properly cared for, spa
water can be responsible for common ailments like rashes and urinary tract
infections. It can also cause cloudy water and damage the spa surface and
The previous paragraph was not intended to scare you, but to educate and
stress the importance of testing the water and keeping it balanced. So,
to help you get a handle on what water balance means, and how you can maintain
it, let's look, one at a time, at the factors that shape your water quality.
As you know things such as bacteria and viruses like to grow in any kind
of water especially hot water.
used to effectively disinfect and keep water smelling fresh. The two most
popular ones are chlorine and bromine. You can test these by using a test
kit or test strips. Proper reading for chlorine is 1.5 - 3.0 PPM and 3.0
- 5.0 PPM for bromine.
These are non-chlorine
that eliminate odors and reduce irritating contaminants for fresh, clear
water. Remember because of the high temperatures and heavy bather loads,
spas require higher sanitizer levels, as well as heavier oxidizer doses
to eliminate bather waste and maintain clear, sparkling water.
Some consider this the most important component of water balance. It measures
how acidic or basic your water is. If it is not kept in check you run the
risk of damaging your equipment, i.e. heating elements, pump seals, and
the internal works on gas fired heaters. Listed are the most common problems
associated with both high or low pH levels:
|High pH Readings
||Low pH Readings
|Poor Sanitizer Efficiency
||Poor Sanitizer Efficiency
||Skin and Eye Irritation
|Shorter Filter Runs
||Etched or Stained Plaster
|Skin and Eye Irritations
||Destruction of Total Alkalinity
The ideal pH range for spas is 7.2 to 7.8. Any reading below 7.2 means your
water is acidic. To correct this you would add
Spa Up. If the
pH reading is above 7.8, it means the water is basic or alkaline. To bring
the pH level down you would use
Spa Down. Another
pH balancing product is called
pH Balance it
works great following some simple instructions included. Once again to achieve
these readings, you will need a test kit or test strips. It is also best
to get your sanitizer level at a reasonable measure before testing the pH.
IMPORTANT NOTE: Before adding any chemicals to adjust your pH levels, the
total alkalinity must be balanced first.
Sounds confusing? It's not, let us explain.
If you thought pH was important, you were right. But, total alkalinity is
even more important.
The total alkalinity is the buffer of pH, if it is not balanced correctly,
the pH will not give you a correct reading. Total alkalinity is the ability
to control pH.
Here is a simple way to understand the difference between pH and total alkalinity:
Think of the pH as the thermometer on your furnace's thermostat. The thermometer
measures the exact room temperature. If it's a little cooler than you like,
you turn the thermostat up. You have just displayed the ability to control
the temperature. Total alkalinity is like the thermostat, in that it gives
you the ability to control pH. This is why you test and adjust the total
alkalinity before even touching your pH test kit.
Your goal? To keep total alkalinity readings inside the acceptable range
of 80 to 120 PPM. If you suspect your pH level to be a little high, then
try for a higher reading of 150 PPM when testing the total alkalinity.
Why? Because pH-lowering chemicals will lower the total alkalinity as well.
If your total alkalinity reading is below 80 PPM, then you will use
Spa Up. If
you got a reading above 120 PPM, then
Spa Down is
what you will use. Again, to achieve these readings you will need a test
kit or test strips.
Now, you ask, what would happen if I didn't keep the total alkalinity balanced?
Let's take a quick look at the problems that can result.
|High Total Alkalinity
||Low Total Alkalinity
|Hard to Change pH
||Rapid Changes In pH
||Skin and Eye Irritation
|Skin and Eye Irritation
|Poor Sanitizer Efficiency
Sometimes referred to as "total hardness", calcium hardness is a measurement
of minerals in your water including calcium and magnesium. You do want your
water to have some level of hardness. If the water does not have enough
calcium, the water will draw from other minerals, including copper, aluminum
and iron, (e.g., heating elements, pump seals, and internal parts on gas
fired heaters). This will result in equipment corrosion. If there is too
much hardness, you will see scale formation on the spa's interior and the
water will take on a cloudy appearance. Because of this, it is recommended
that you fill your spa with water from a softener instead of tap water.
So what should the calcium reading be? Between 100- 250 PPM's for acrylic
finish, and 250-450 PPM's for plaster finish. Let's look at some potential
problems if it goes unchecked.
|Hardness too Low
||Hardness too High
|Deterioration of Metal Components in Spa Equipment
||Scale Formation On Surfaces
If your water is high in calcium there is no known way to lower it using
Spa Defender gives the best preventive maintenance against scale formation.
Also, if your water is high in calcium this is where you may want to use
water that is treated by a softener to fill your spa. In many cases you
will find a low calcium reading that can be adjusted by using
To make any adjustments to calcium hardness you will need a
test kit or test
Well that's all! All the really important stuff anyway. There are other
chemicals available that will help keep your water clean, clear and free
from oily scum. These can be found in the
Remember, test your water regularly, but most of all, enjoy your spa!