Hot Tub Filtration

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Hot Tub Filtration is a major key in keeping your water clean, clear, and inviting. There are two dominant filtration technologies used today: circulation pumps and programmed filtration.

Circulation Pump Technology

‘Circ’ pumps operate independently from the main water movement pumps. While not therapy pumps, they serve to continuously clean water through a dedicated filter before being returned to the tub. The logic is that by continuously filtering, water will stay cleaner. I see flaws in some manufacturers’ systems. Some circ pumps will only turn 5000 gallons of water in a 24-hour period. This equates to just 3.47 gallons per minute returned via a single orifice. Therapy jets are not used. That sounds like a lot of filtration, but on a 500-gallon hot tub, it’s ten turns of water a day. With hot water, you want considerably more—as many as forty turns. This lack of filtration often requires the main system to perform extended purges of the plumbing lines. I call this catch-up filtration via user-mode.

Fortunately, many manufacturers have gone to higher flow circ pumps and many move twice the water volume. That’s much better and allows a larger diameter plumbing line, reducing calcium build-up that could clog the circ pump. Still, there isn’t enough filtration, requiring those extended purges. A selling feature is that circ pumps often draw less than one amp and cost little to run. The downside is when the purge cycles are forced to run much longer than necessary. Normal purging takes just a few seconds, replacing water in the lines with fresh water from the tub. Extended purges in user-mode often run several minutes, giving back the savings.

Programmed Filtration

Older programmed filtration relies on factory settings to automatically turn a hot tub on for a designated number of hours. A two-speed, single pump unit runs on high for a few seconds, purging the line. Then it settles into a low-speed cycle that moves upwards of thirty gallons per minute. It then shuts off until the next factory-set cycle begins. A multiple pump tub does the same thing, but only one pump runs after the purge. The system works fine, however there is little user control of when cycles start. Several manufactures still provide this basic control system.

Hot Tub Filtration

The next advancement allows users to select how long normal cycles will be and also introduces economy settings. During normal cycles, if the water temperature drops, the unit turns on and heats to the set temp. In economy mode, you get your filtration cycles, but water doesn’t reheat until it falls to a set temperature. The only drawback is when you want to use your tub but have to wait for it to reheat. Still, this is a definite upgrade and a popular technology.

Better manufacturers today use programmed filtration that makes older systems look simplistic.  Topside controls on our Saratoga Spas/Hot Tubs allow the user to easily enter the time filtration begins. Then, how long it is to run and what time to stop. It’s an easy-to-use digital system that also links via app to your smartphone. It’s easy to adjust your cycles, water temperature, or your hot tub’s status, no matter your location. Jumping on a plane in Denver? Adjust your tubs temperature so it will be ready when you get home.

Eastgate Pools. What We Believe.

To have a safe, sanitary environment in your hot tub, you need three things: Sanitization, Circulation, and Filtration. Eastgate Pools & Spas can order hot tubs with either circulation pump technology or programmed filtration. We currently choose programmed filtration as we believe it provides the best filtration and circulation and is highly economical. Coupled with a great sanitization, such as the Simple Spa program, it’s a logical choice. Could this philosophy change? Sure. Eastgate Pools & Spas is always looking to provide the best, most efficient systems available. Our eyes are always open and as technology marches on, things change.