Overview of Dual Spa Filters
Let's assume you have a spa on our vacation home that your family often use . When you're not using it, you occasionally have a hard time keeping the water clean. This issue prompted you to double the filtration on the spa.

Here's a guide on how to add a second filter to your portable spa.


Adding a second spa filter

A portable spa's filter comes in handy with the suction side of the pump. It's commonly known as a skimmer filter, and it features a built-in bypass feature that allows the jet to flow without interference.

Inline spa filters are available in various sizes, ranging from 25ft to 100 sq ft. Most of them feature a high capacity cartridge that can fit under the cabinet.

There are 3 main ways to install a secondary spa filter, under the cabinet, outside the cabinet, or top loading, through the cabinet corner.



Having a second filter would be a bit of a chore, as well as re-plumbing the pump. To clean the filter, just close the valve and remove the cartridge and canister.

You can use an inline filter with a bottom connection, but the top mount style is usually easier to use.

If you're not sure where to find a spa pressure filter, follow these simple instructions. It's also important to ensure that the filter is positioned in the proper direction of the flow indicator.



If your spa doesn't have room inside the cabinet, then go with the outside filter, which is located near the cabinet. It's a great choice if you don't want to go with the traditional hot tub design. Also, it allows for a larger filter to be installed.

A secondary spa filter can be installed outside the spa cabinet by using a 2" hole saw to cut through the cabinet. Both the pipe coming from the pump and the return line should be drilled through the cabinet.

Ideally, use 2" or 3" flexible or rigid PVC pipe to avoid adding too much resistance. However, use as few as possible to minimize the amount of resistance.

Use fresh PVC glue and primer. Deep socket couplings are not drain fittings.



Spa components with a square cabinet have molded corners. Top load spa filter systems are those that are designed to keep the cartridge in place while the spa is being used.

These high-quality spa filters are made to fit a 6-3/4" hole in a spa shell. They are typically cut using a jig saw or a Dremel tool.

Top load filter are usually placed over the water level. They are not underwater. Spa Skimmers are also used for removing debris from the water.

Top Load spa filters have a built-in plumbing connection point that's located on the bottom of the filter. The size of the pipe can be varied depending on the size of the filter.

Use fresh PVC and primer, and only use pressure fittings if they're deep socket couplings.

If your spa doesn't have a filtration system, or if you have a hot tub that doesn't have one, consider adding a second filter.


If you have any other questions about pool and spa products please do let us know - we are here to help!

Leave a comment