PCD50 / C-7451 / FC-3084 / Caldera 33016
50 sq ft replacement filter cartridge • 7″ OD × 10.75″ long
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PCD50 replacements on Amazon
The buttons below pull up Amazon results for each cross-reference part number. Same physical cartridge, different stickers, often different prices. Cross-shop and pick the cheapest option that has solid recent reviews.
Cross-Reference & Interchangeable Part Numbers
| Brand | Part Number | Type |
|---|---|---|
| Pleatco | PCD50 | Primary |
| Unicel | C-7451 | Equivalent |
| Filbur | FC-3084 | Equivalent |
| OEM | Caldera 33016 | Original Equipment |
Always verify dimensions and end-cap type before purchasing a replacement.
Frequently Asked Questions
What are the dimensions of the PCD50?
The PCD50 is 7 inches in outer diameter, 10.75 inches long, with a handle top and a slip-fitting bottom. Total filtration area is 50 square feet. Before ordering, pull your existing cartridge and measure it yourself, or check the label inside the housing. OD and length both have to match within about an eighth of an inch, and the end-cap style needs to match exactly so the cartridge seats properly when the lid closes.
What other part numbers are interchangeable with the PCD50?
PCD50 is the same physical cartridge as C-7451, FC-3084, plus OEM versions like Caldera 33016. Same dimensions (7" × 10.75"), same handle top, same slip-fitting bottom. The Pleatco, Unicel, and Filbur boxes ship the same media inside, just with different stickers. The only thing to watch is the end-cap style: if a cross-reference has a slightly different cap design, it may not seat right in your housing.
Is the Caldera 33016 the same filter as the PCD50?
Yes. Caldera 33016 is an OEM number, the code the tub or pool builder stamps on the cartridge they ship. The filter itself is made by Pleatco, Unicel, or Filbur, so Caldera 33016 and PCD50, C-7451, FC-3084 all point to one interchangeable cartridge. Buy whichever is cheapest with solid recent reviews, and just check that the dimensions match your old cartridge before you order.
How often should I replace the PCD50?
Most filter cartridges last between 12 and 24 months. Pull the PCD50 every few months for a hose rinse, soak it in cleaner quarterly, and replace it when the pleats are torn, channeling, or won't come clean. Bather load, water chemistry, and how often you actually clean it all matter more than the calendar.
How do I clean the PCD50?
The PCD50 has a built-in handle on top, which means you can pull it without touching the media. Pull the cartridge from the housing and hose it down. Hit the pleats from above at about a 45-degree angle so water rinses debris out instead of packing it deeper, and work top to bottom while rotating the cartridge. Skip the pressure washer. The high pressure tears or collapses pleats, and once that happens you've lost media that doesn't come back. Every few months (or at every water change, whichever comes first), do a deep clean: overnight soak in a hot tub filter cleaner, then a thorough rinse. If your cartridge has a closed end cap, let it dry before reinstalling so you don't trap moisture inside the cartridge core.
Which hot tubs and spas use the PCD50?
Pull your existing cartridge and read the part number off the end cap, or check the label inside the filter compartment. That's the most reliable way to confirm compatibility.
Dimensions
Specifications
| Outer Diameter | 7″ |
|---|---|
| Length | 10.75″ |
| Top Type | Handle |
| Bottom Type | Slip fitting |
| Filtration Area | 50 sq ft |
| Primary Brand | Pleatco |
| Part Number | PCD50 |
Fitment notes
Swivel handle top, 2-inch male slip fitting on the bottom. This is the original style Caldera 50, superseded by the PCD50N, which drops the slip fitting for a plain 2-2/3 inch opening. Unicel states its C-7350 (the PCD50N equivalent) can be used as a replacement for this cartridge. Pleatco's sheet gives the length as 10-9/16 inches against Unicel's 10-3/4.