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Using Test Strips
Spa Water Analysis
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AquaChek premium quality spa test strips Maintaining spa water quality depends on the accuracy of water analysis. In the past, spa test strips were considered by some to be less accurate than complicated liquid test kits.Great strides have been made making test strips the preferred water testing method. Test strips are easier to use, and more economical than cumbersome liquid test kits.

There's no equipment to clean. You never have to keep track of various liquid chemical reagents... a drop of this, two drops of that. Hot tubbing is for fun and relaxation, so let's keep water testing simple and easy as possible. This is not rocket science!

Why We Test Spa Water

Analyzing hot tub water allows us to balance the chemical properties so that it is neither too alkaline nor too acidic, for both comfort and equipment protection. It also allows us to maintain a spa sanitizer system to keep the water healthy and free of harmful microorganisms.

Total Alkalinity (TA) is always adjusted first, then we look at pH. (Correcting TA often brings pH in line). Complete instructions for water balance are found on our Prep & Maintenance page.

There are now also new test strips to monitor bacteria.

Simple Testing Procedure

If using a conventional sanitizer such as bromine, check spa water weekly. If using Cleanwater Blue sanitizing system, testing is required only twice a month. Note: Read the instructions on the bottle. Testing procedures vary by test strip brand.

Compare test strip color with chart on bottle
  • Allow spa to circulate for a minute or two, then take a sample of spa water in a clean plastic drinking glass-- a few ounces will do.
  • Remove a spa test strip from the bottle, and recap tightly.
  • Dip the strip in the water just deep enough to wet the test pad(s) used, and remove according to bottle directions.
  • Remove excess water by shaking the strip once, briskly (again, check the bottle directions).
  • Hold strip horizontal, pad side up, for 15 seconds (or per bottle instructions).
  • Make color comparisons with bottle chart.
  • Adjust spa water as necessary. See Prep & Maintenance instructions.
  • For most accurate results, allow water to equilibrate several hours or overnight after adding balance chemicals, then retest.

Watch your Fingers

Dip test strips quickly Be sure to wash your hands before performing the test. Bromine, chlorine, or other chemical residues on fingers can skew the test results. Never put a wet finger into the test strip container. This will contaminate the unused strips.

Store Strips Properly

Store test strips at room temperature Don't store your test strips outside. Keep them at room temperature, dry, and away from direct sunlight. Cap the bottle tightly right after removing a strip-- don't wait until you are done testing.

Use Fresh Strips

Check test strips bottle for date Check the date on the bottle and replace expired strips.  Beyond that date, you may get false readings resulting in wasted chemicals, or improper water balance.


For Chlorine & Bromine Users Only

When buying test strips, make sure they measure Total Bromine and/or Total Chlorine. Not all brands of test strips do. Total bromine/chlorine is the sum of free chlorine/bromine and combined chlorine/bromine. Our test strips test for total.

Bromine Testing
Free bromine is the most active form of the sanitizer. When it reacts with contaminants, it becomes combined bromine. Yet combined bromine is still about 80% effective, and can be converted back to free bromine by shocking the water with non-chlorine shock, such as our OxySpa. You need test strips which test Total Bromine. Old technology strips which test only free bromine can falsely indicate the need for adding more bromine, when there is plenty of combined bromine still present in the water.

Chlorine Testing
Chlorine testing is a different story. Only free chlorine (the form of chlorine you add to the water) is an effective sanitizer. As with bromine, when free chlorine reacts with contaminants, it becomes combined chlorine, but then has very little sanitizing ability. Combined chlorine can cause irritation, and has a strong odor. Make sure your test strips measure both free and total chlorine, so you can determine the amount of combined chlorine present.

[Total Chlorine] - [Free Chlorine] = [Combined Chlorine]


Test Strips The Spa Depot's wide variety of test strips including AquaChek, are the finest quality, most accurate spa and pool water tests you can buy. A full range of tests at reasonable prices including our new Water Safe bacteria check.

spa customers write  Consumer Reviews
AquaChek Test Strips
"I would just like to say that I have received the best customer service that I have received in a very long time. The guy in your Tech Support was a big help in helping me resolve the problems I was having with pH out of whack. He helped me select the right Aqua Chek test strips (which were a great buy, by the way!) and got me all set up with the right chemicals to keep things in balance and didn't try to sell me stuff I did not need. No problems since."

Trace Ives
Boulder, CO

Spa Depot, The, Spas & Hot Tubs - Dealers, Olympia, WA

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