swim spa current

Complete guide to understanding swim spa currents

Swimming is one of the best ways to strengthen muscles and improve cardiovascular health–and it’s something that everyone can do! Swimming pools have been around since ancient times when people would fill large pools with water from nearby lakes or rivers so they could cool off during hot summer days (and nights).

Backyard in-ground pools, though, aren’t always practical for swimming. The standard pool is not large enough for lap swimming. And, depending on where you live, you might be able to hop in a few months out of the year. 

Enter the swim spa. Whether you’re a seasoned swimmer or just enjoy getting into the water, swim spas are a great way to incorporate continuous laps or water exercise into your routine. Designed for year-round use, Master Spas swim spas provide a quality swimming experience in the convenience of your backyard.

However, you might have questions about how to use a swim spa. How does the swim current work? Do you need a tether to swim in a spa? What makes a good current? How fast can you swim in a swim spa?

Choosing a swim spa with a quality current and features that complement your lifestyle will not only allow you to train at home for competitions, triathlons, or just to stay in shape. You’ll also have a space to unwind and reinvent family time.

swim spa current
Swim spas feature a continuous flow of water, which creates resistance for stationary swimming and water exercise.

How does a swim spa work?

A swim spa provides the benefits of an at-home pool with the therapy of a hot tub. There is a therapy side with ergonomic seating and built-in massage jets. There’s also a larger swim area for swimming, exercise, relaxation, and family fun. 

One thing that makes a swim spa unique is the ability to swim against current. It’s like a treadmill for swimming — you can enjoy a great workout while staying in the same place. 

Master Spas manufactures two lines of swim spas: H2X Fitness and Michael Phelps swim spas. With both lines, swim pumps move water to create a continuous flow of water. This water current helps you stay in place while swimming or exercising. 

The speed of the water can be adjusted using the control panel and diverter valves, which direct the flow of water to particular jets.

swim spa current
Master Spas swim spas are designed to maximize the return of the water and the flow of the current.

What makes a good swim spa current?

Jets, propulsion systems, paddlewheels — there are a number of categories of swim systems. And when comparing brands, each might have a proprietary name for the swim current system. 

If you are trying to select the best current, you might feel overwhelmed by the options. After all, you just want to swim.

The right swim spa current is the one that helps you achieve your fitness goals, no matter what they might be, and it does so by providing a pleasant experience during every session in the spa.

However, there are a few key areas to consider when comparing swim spas and the swim systems — strength of the current, the amount of turbulence, the size of the swim “lane,” and the ability to control the current 

swim spa current
A key feature of a swim spa should be the ability to control the water current. Using the touchscreen panel, you can control the speed of the pumps on your Master Spas swim spa.

Strength of swim current

The strength of a swim spa current typically refers to how fast the water moves, whether it’s through jets or a propulsion system. The more water that moves — and moves at a faster rate —  can make it easier to swim faster in a spa. However, the other swim spa considerations can affect whether you can swim at your pace and without a tether.


When you are swimming in a swim spa, you want the current to be smooth. In addition, you want to have good visibility — being able to see the bottom of the spa as you swim. A swim current that’s turbulent will look choppy, and you will feel like you are being pushed around. You might also feel like you are swimming over the current instead of against it.

Why would a swim current have a lot of turbulence? The amount of air introduced into the stream of water can also add turbulence. The water might move with more force but the trade-off is a quality swim experience.

Master Spas’ Challenger series, for example, has an airless jet system. The swim current is smooth and wide, with increased visibility compared to other brands. And without air in the water flow, you can swim faster without the turbulence.

Swim channel

Among the benefits of a swim-in-place pool is that you are trading lap lanes at the local pool for a private swim session. But you still might have to stay in your lane in a swim spa.  A “swim lane” is the area of the swim spa where the actual swim current is produced. The wider the swim channel is, the easier it is to swim against the current and not get bounced around.

Master Spas swim spas were designed so that the water current creates almost a triangle-shaped current. The farther away from the current, the wider the swim lane. Many find that the “sweet spot” is when the swim jets are about a foot away from their fingertips. 

Controlling the current

Every swimmer is different. And each swimmer might feel different, depending on the day. One day, a certain swim pace can feel easy. The next day, it might be a challenge. When you are swimming in a swim spa, you want to be able to control the swim current. 

No matter how fast the water flows, you can’t realize the benefits if you can’t control it. You want to be able to vary the speed and even manipulate the jets of the swim system. 

Master Spas swim spas feature an easy to use touchscreen panel, which allows you to set the swim speed. You can also individually control the swim pumps for a more custom swim experience.

spa jets
Swimming in a swim spa will give a feeling most similar to a river’s current.

How does a swim spa current work?

The water current of a swim spa is what allows you to enjoy a stationary swimming experience. Master Spas swim spas are designed to maximize the flow of water being created at the swim jets or propulsion output grate. The current is designed to be wide, smooth, and deep — allowing you to swim with good technique against the flow of water. There are some characteristics that swimming in a spa will have that are comparable to open water or lap pool swimming.

Swimming in a swim spa will give a feeling most similar to a river’s current. The swim pumps will work at a consistent level to keep the water flow output consistent. However, some swimmers may notice or perceive that the strength of the swim current can have variation. Don’t worry! There is nothing wrong with your swim spa and within a few seconds, you’ll be back to swimming at a strong pace.

This experience occurs in swim spas as the water flows towards the opposite end and must split, making its way back towards the current output end of the swim spa. As this happens, the body of water is developing two, split, circulating flows which can lead to the appearance, perception and feel of changes in current flow or strength. If standing back to watch these flows, you can even notice how the water can tend to pool some at the opposite seating / step in area and then shift back toward the current flow end. This is simply a natural and physical trait of swim spas.

Just keep swimming and enjoy the feeling of rest that you might notice.

Swim spas are great for people who want a workout in the comfort of their own home, and they can be used year-round thanks to the design, insulation, and built-in heating system. 

winter swim spa use
With a Master Spas swim spa, you can swim, exercise, and relax in the comfort of your backyard.

How to buy a swim spa

Do you want to be able to swim, exercise, and relax at home? Having a Master Spas swim spa allows you to swim on your schedule while adding a fun factor to your backyard. You can click here to find out more about the benefits of hydrotherapy and relaxing in a hot tub. Or, contact your local Master Spas retailer to learn more about swim spa ownership. Wondering how much a swim spa costs? You can request a quote here.