Bullfrog 10-2870 Filter Cartridge
Bullfrog OEM number • 35 sq ft • 8″ OD × 5.75″ long
10-2870 is Bullfrog's number for this cartridge, not a part you have to buy from Bullfrog. The filter itself is a 35 square foot cartridge measuring 8 inches across and 5.75 inches long, and Pleatco, Unicel, and Filbur all build it. If you read 10-2870 off an old cartridge or found it in your manual, any of the numbers below drops into the same housing.
Bullfrog also lists 10-2785 against this cartridge. Different numbers on paper, same filter in the box.
Fitment notes
Semi-circular handle top with a 2 inch SAE threaded bottom. Bullfrog A-Series and R-Series before 2018. Unicel reaches this cartridge from Bullfrog OEM 10-2870, resolving it to the 8CH-951 at 8 by 5-3/4 inches, and states that the original cartridge for that fitment held 35 sq ft, which is where the part number comes from. Unicel's own 8CH-951 is the same envelope with 40 sq ft of media. Do not order against the 8CH-950 or Bullfrog 10-1035: both belong to the PBF50, which is a quarter inch longer and rated 50 sq ft. Bullfrog 10-2785 comes from the site's seed data and appears in neither cross-reference sheet. Filbur publishes no equivalent for this cartridge in either sheet; its FC-0536 belongs to the PBF50.
What to buy instead
Replacements for the Bullfrog 10-2870
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 |
|---|---|---|
| Bullfrog | 10-2870 | The number you searched |
| Pleatco | PBF35 | Aftermarket equivalent |
| Unicel | 8CH-951 | Aftermarket equivalent |
| Bullfrog | 10-2785 | Other OEM number |
Full specs, the cartridge diagram, and the complete compatibility list live on the PBF35 cartridge page. You can also see every 8″ × 5.75″ cartridge if you are checking a measurement rather than a part number.
Equipment that uses this cartridge
Looking for a different model? Browse every Bullfrog model we cover.
Frequently Asked Questions
What filter replaces the Bullfrog 10-2870?
The PBF35 replaces it directly, and so does every cross-reference for it: 8CH-951. All of them are the same 35 sq ft cartridge at 8" outer diameter and 5.75" long. Buy whichever is cheapest at the time with solid recent reviews. The same cartridge also shows up as Bullfrog 10-2785, so those are not different filters either.
Is the Bullfrog 10-2870 the same as the PBF35?
Yes, physically the same filter. Bullfrog 10-2870 is an OEM number, meaning it is the code Bullfrog put on the cartridge that shipped with the equipment. Bullfrog 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 Bullfrog 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 Bullfrog 10-2870?
8 inches in outer diameter, 5.75 inches long, with 35 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.
Data updated September 2026