Claralys

Claralys spa and hot tub filter cartridges

Claralys makes replacement filter cartridges for portable spas, hot tubs and swim spas — the pleated media inserts that sit inside the skimmer housing or filter canister and catch body oils, hair, pollen and fine dirt before the water returns to the shell. Because spa water volumes are small and bather loads are high, the cartridge does a disproportionate amount of work, and it is usually the first component that needs attention. The range here is built around the sizes and fittings that appear most often in European and imported spas, so an existing cartridge can normally be matched on dimensions and end-cap type rather than on the name of the tub.

What the range covers

Seven cartridges are listed, split across two naming families that correspond to the two common mounting styles found in spa filtration.

• CRB series — drop-in pleated cartridges in the familiar spa format, including the CRB25, CRB35, CRB50 and CRB75. These are the replacements most often quoted against PRB-coded originals, with the CRB25 matching PRB25 and the CRB75 matching PRB75.
• CWW series — cartridges shaped for Waterway front access skimmer housings, including the CWW10, the CWW50L for PWW50L and RD50 style positions, and the CWW50P3 with a threaded base.
• Screw-in fittings — the CWW50P3 is a 50 sq ft screw-in cartridge, so it threads directly into the skimmer body rather than resting on a seat.
• Stated sizes — the CRB35 measures 127 x 235 mm, while the CRB50 and CWW50P3 are both rated at 50 sq ft of filtration area.

Matching a cartridge to your spa

Spa manufacturers rarely print a part number inside the filter bay, so the safest method is to measure the cartridge that is already fitted. Four details decide the fit: outer diameter across the pleats, overall length from end cap to end cap, the inner diameter of the core opening, and the style of each end — open handle, closed flat cap, cone, or a threaded base. A cartridge that is a few millimetres too long will not allow the lid to seat; one that is too short will let unfiltered water bypass the pleats altogether.

The square-foot figure describes the filtration surface area, not the physical size. Two cartridges with the same diameter and length can carry different ratings depending on how many pleats are folded into them. A higher area generally means longer intervals between cleans for the same bather load, but the figure should never override the physical measurements — the cartridge has to seat correctly first.

• Front access skimmers — these take a cartridge that slides in horizontally or vertically behind a removable door, which is where the CWW sizes are normally used.
• Threaded positions — if the old cartridge has a male thread moulded into one cap, a drop-in equivalent will not seal; a screw-in version is required.
• Twin set-ups — some spas use two cartridges of different sizes in one bay, so both should be measured separately.

Cleaning, wear and when to replace

Pleated spa media is designed to be rinsed. Hosing the pleats open from top to bottom every one to two weeks removes the loose debris, while a periodic soak in a dedicated filter cleaner breaks down the oils and lotions that rinsing leaves behind. Avoid household detergents, which foam badly once the cartridge is back in circulation.

A cartridge reaches the end of its life when the pleats stay grey after soaking, when the fabric feels soft or starts to split along a fold, or when an end cap separates from the media. Flattened pleats and a cracked core are also terminal — both allow water to short-circuit the filter. Keeping a second cartridge on hand means one can dry fully between cleans, which extends the service life of both.

Claralys at PoolParthub.com

Here you will find the Claralys cartridge sizes that cover the most widely used spa filter positions, from the compact CWW10 through the 50 sq ft CRB50 and CWW50P3 to the larger CRB75. Each listing names the original coding or the dimensions it replaces, so a cartridge can be identified from the one currently in the tub.

They are stocked because filter cartridges are a recurring purchase rather than a one-off repair, and because a correct-fitting replacement does more for water clarity and pump life than any chemical adjustment. Measure the old cartridge, check the end caps, and order the matching size.