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With all the additional expenses that come with owning and maintaining a hot tub, is a pre-filter really a necessity?
You should use a pre-filter to filter the water while filling your hot tub. Pre-filters help to remove contaminants such as suspended solids and heavy metals, which are commonly found in garden hose water. Pre-filters produce water that is cleaner, fresher, and requires fewer chemicals to balance the water chemistry.
Something you probably don’t realize is how your garden hose can affect the number of toxic chemicals in your water.
Pre-filters go a long way to helping reduce contaminants, but I recommend investing in a polyurethane hose too.
Why you need a pre-filter for your hot tub water
The water from your backyard hose contains a vast array of bacteria, chemicals, and toxic organic compounds that are harmful to you and your hot tub.
Pre-filters are a simple and inexpensive solution to this problem. They attach to any standard garden hose to immediately provide fresher and cleaner water.
I like to use the Camco Taste PURE XL inline pre-filter. The XL model has a higher flow rate for faster filling and provides twice the filtration when compared to most standard water filters.
These pre-filters are widely used by the RVing community for purifying their water while out on the road. They’re so effective that they make dirty garden hose water safe for consumption, so you can see how beneficial they are for your hot tub and its components.
The Camco pre-filter uses an environmentally responsible product called granular activated carbon (GAC) to absorb and remove a variety of these contaminants.
The GAC filters particles that are greater than 20 microns (0.02mm / 0.0007 inch), which usually amounts to the removal of as much as 98 percent of the contaminants.
By removing the vast majority of harmful contaminants from the water, you save money on start-up chemicals that would ordinarily be required to cleanse the hose water to make it safe for your hot tub.
Using fewer chemicals recoups on the investment cost of purchasing a pre-filter and saves you valuable time not having to go round in circles trying to balance the water chemistry.
Cleansing the water before it reaches your hot tub also protects the main filter cartridge. This helps it to last longer and makes your life easier during weekly filter cleans.
Each pre-filter can purify up to 2,400 gallons (9,000 liters) of water, so you’ll only have to replace it once a year when draining your spa water every three months.
If you live in an area with hard water, I recommend using a stain and scale product alongside the pre-filter to help eliminate the harmful effects of heavy metal impurities.
There are several other steps you can take to keep the water as clean and fresh as possible, which I’m going to cover later on.
Are hot tub pre-filters really necessary?
The water from your garden hose is usually the exact same water found inside your home; however, the pipes and fittings that carry the water are not regulated in the same way.
Pre-filters are necessary in order to remove harmful contaminants found in unregulated water sources. They also remove chemicals that have been leached into the water from PVC hoses. This protects your main filter cartridge and prevents clogged pump impellers and a fast decline in the water quality.
If your home is fitted with a water purification system, the bad news is that they don’t usually extend to outside water sources.
Hose water is contaminated
The Environmental Protection Agency monitors the drinking water supply through the Safe Drinking Water Act, performing regular tests to check for impurities and the presence of chemicals.
But you’re not going to use the hose water for drinking, right?
Unfortunately, many of the contaminants found in hose water are just as harmful to your hot tub as they are to you, which is why they need to be removed.
- Chlorine by-products
- BPA (bisphenol A)
Unless you live in a part of the world that enjoys extremely soft water, you should always have an inline pre-filter attached to your hose.
They’re most effective in hard-water areas or for homeowners that fill their hot tub from a groundwater well.
PVC hoses contaminate water
To make matters worse, most hoses contain bacteria, mold, and elevated levels of toxic chemicals. These contaminants can leach into the water if your hose is not made from NSF International-listed polymers.
A study conducted by the Ecology Center revealed that these dangerous levels of hazardous chemicals were caused by the flexible part in PVC hoses.
During the study, 21 garden hoses were tested for lead, cadmium, bromine, chlorine, phthalates, and BPA.
These chemicals have been linked to birth defects, impaired learning, liver toxicity, premature births and early puberty in laboratory animals, among other serious health problems.ecocenter.org
The study concluded that polyurethane hoses were among the safest on test. Garden hoses labeled as “drinking water safe” were found to be far safer than PVC hoses but still contained phthalates plasticizers.
Top-rated hose: Water Right Professional Coil Garden Hose
Traditional polyurethane hose: ELEY Polyurethane Garden Hose
Worst performing hoses
The following are the three hoses listed by Ecology Center as being the worst performers. If you have one of the following hoses, I’d change it immediately:
- The Home Depot retailed HDX Utility Hose
- Walmart retailed Swan Hose Reel Leader Hose
- Lowes retailed Apex NeverKink
3 effective ways to minimize contaminants in hose water
Removing 98 percent of the impurities is certainly a big leap in protecting your expensive hot tub and its components. But there are a number of steps you can take to further minimize the contaminants.
Let the water run – Before filling your hot tub, allow the water to run for a few minutes to get rid of any water that’s been sitting in the hosepipe and plumbing. Most outdoor plumbing fixtures are made from brass, which usually contains lead. Again, most of the contamination from the faucet (tap) can easily be removed by letting the water run for a short time first before filling. If your hose sees a lot of use, replace the brass faucet regularly.
Store hose away from direct sunlight – Sunlight and warm temperatures increase the rate of degradation, resulting in harmful toxins leaching into the water. Store your hosepipe in an area that is shaded and cool to prolong its life and ensure that there are minimal contaminants in the water.
Invest in a polyurethane hose – As mentioned, good polyurethane hoses are free from toxic chemicals such as lead, phthalates, and BPA, so you don’t have to worry about them getting into your spa water. Besides polyurethane hoses being highly durable, their other benefits include kink resistance, excellent flexibility, abrasion resistance, and stability under a wide range of temperatures.