Hot Tub Supply Spa Depot
Changing Water
Draining Intervals for Hot Tub Spas
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Most spa owners change their hot tub's water every 2 to 4 months.  This is primarily because over time, salt from perspiration and other non-organic contaminants-- the Total Dissolved Solids or TDS, will increase to levels causing cloudiness or other problems.

Although organics are destroyed by your sanitizer system, TDS levels continue to increase over time. But how do you really know when it's time for draining?

Compare test strip color with chart on bottle Maintaining your spa water balance & sanitizer, along with proper filtration will maximize the time between water changes.   Its time to change the water when the TDS level exceeds about 1500 PPM.  These levels can be checked with TDS test strips.
Another useful tool, our WaterSafe Bacteria Test Strips are a great new way to periodically verify sanitary spa water before problems arise. Water Safe bacteria test strips

Estimating Drain Intervals

Using your spa's water volume in gallons and estimated bather load, you can easily determine the estimated number of days between necessary water changes with the simple equations below:

Handy Formulas

First, divide your total spa gallons by 3. Divide this result by your Bather Load, which is the average number of bathers per day. The final result is the estimated number of days between water changes recommended for a properly maintained spa or hot tub.

Example 1: Residential Spas:

hot tub bather load

Example 2: Commercial Spas:

hot tub bather load

Please keep in mind that these are estimated guidelines only.  The formulas assume that your hot tub spa is properly maintained, and water is balanced and sanitized. Other factors such as user hygiene and local water quality will also affect drain intervals.  If users shower before using the spa, water changing intervals will be longer. Local regulations may govern water change intervals for commercial spas.

Hot Tub Drains

access door Most spas have a drain bib (a plastic faucet) inside the removable access panel.  Some spas have no drain and must be siphoned.  
external drain Most Belize spa models feature the Easy Drain so that they can easily be drained by attachment of a garden hose externally.  

Flush Your Spa's Plumbing with Every Water Change

You do your best to keep your spa clean and sanitary, but what you don't know is that the INSIDE of your spa's plumbing system is likely coated with oily film, contaminants & grime. Spa System Flush dissolves harmful biofilm

By flushing your spa's inside plumbing, jets, and heating systems before each draining with Spa System Flush you will achieve the cleanest possible water environment.  You'll truly be amazed at what this product removes from an otherwise spotless hot tub.

Self-starting Shake-a-Vac Use the Shake-a-Vac II to clean or drain portable spas, above ground pools, pool covers, inflatables & soft spas. This is the only vac we have found that actually starts its own siphon.  We were very skeptical... until we tried it.  Now we love it, and we think you will too.

spa customers write  Consumer Reviews
WaterSafe Test Strips
"I keep our spa as clean as possible but we have kids so these bacteria test strips are reassuring."

Cindy Stevens
Twin Falls, ID

"We use it daily to vacuum gritty sand from the bottom of the spa.  There was no easy way to get it out before.  Although our spa has its own drain, by using the Shake-a-Vac at the same time it empties the water twice as fast."

Randy Parkhurst
Lincoln, NB


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