Marquis 370-0236 Filter Cartridge
Marquis OEM number • 50 sq ft • 5.1875″ OD × 14.125″ long
370-0236 is Marquis's number for this cartridge, not a part you have to buy from Marquis. The filter itself is a 50 square foot cartridge measuring 5.1875 inches across and 14.125 inches long, and Pleatco, Unicel, and Filbur all build it. If you read 370-0236 off an old cartridge or found it in your manual, any of the numbers below drops into the same housing.
Marquis also lists 20044 and 37-0217 against this cartridge. Different numbers on paper, same filter in the box.
Fitment notes
Closed top, 1-5/8 inch bottom hole. Marquis Signature Series 1997-1999, all models. Unicel reaches this cartridge from Marquis OEM 20044 and 370-0236. The 37-0217 number Pleatco prints for it does not appear in Unicel's guide and is likely a misprint of 370-0217. Pleatco's 2008 catalog lists this cartridge as PPM50 without the TC suffix.
What to buy instead
Replacements for the Marquis 370-0236
Each button searches Amazon for one of the numbers this cartridge is sold under. The OEM version is usually the most expensive of the set and the aftermarket versions are the same physical filter, so it is worth checking all of them before you order.
Every number for this filter
| Brand | Part Number | Type |
|---|---|---|
| Marquis | 370-0236 | The number you searched |
| Pleatco | PPM50TC | Aftermarket equivalent |
| Unicel | C-5346 | Aftermarket equivalent |
| Filbur | FC-3638 | Aftermarket equivalent |
| Marquis | 20044 | Other OEM number |
| Marquis | 37-0217 | Other OEM number |
Full specs, the cartridge diagram, and the complete compatibility list live on the PPM50TC cartridge page. You can also see every 5.1875″ × 14.125″ cartridge if you are checking a measurement rather than a part number.
Equipment that uses this cartridge
Looking for a different model? Browse every Marquis model we cover.
Frequently Asked Questions
What filter replaces the Marquis 370-0236?
The PPM50TC replaces it directly, and so does every cross-reference for it: C-5346, FC-3638. All of them are the same 50 sq ft cartridge at 5.1875" outer diameter and 14.125" long. Buy whichever is cheapest at the time with solid recent reviews. The same cartridge also shows up as Marquis 20044, Marquis 37-0217, so those are not different filters either.
Is the Marquis 370-0236 the same as the PPM50TC?
Yes, physically the same filter. Marquis 370-0236 is an OEM number, meaning it is the code Marquis put on the cartridge that shipped with the equipment. Marquis does not manufacture cartridges. Pleatco, Unicel, and Filbur do, and they sell the identical part under their own numbers at a lower price. Match the dimensions against your old cartridge before ordering and you are covered.
Do I have to buy the Marquis version?
No. Nothing about the housing requires an OEM-branded cartridge, and the warranty on your equipment is not voided by using an aftermarket filter that meets the same spec. The reason to buy OEM is convenience, not performance. The reason not to is price, which is often a meaningful gap for an identical part. What matters is that outer diameter, length, and end-cap style all match.
What size is the Marquis 370-0236?
5.1875 inches in outer diameter, 14.125 inches long, with 50 square feet of filter media. Both measurements need to land within about an eighth of an inch, and the end caps have to match so the cartridge seats correctly when you close the lid. Measure your old one rather than trusting a number that has worn off the label.
Last verified August 2026