Mantis Back Porch 35 gal Compost Tumbler Review
Specifications
| Brand | Mantis |
|---|---|
| Compost Capacity | 35 gal |
| Overall Dimensions | 37 x 31 x 26 in |
| Weight | 38 lb |
| Drum Material | Plastic |
| Frame Material | Steel |
| Assembly Required | Yes |
Pros
- Sturdy metal frame
- Low-odor composting
- Pest-contained design
Cons
- Low compost volume
- Less durable plastic drum
- Axis cracking risk
The Verdict
The Mantis Back Porch 35 gal compost tumbler targets low-odor backyard use, scoring 7.6 for overall balance. It uses a pest-contained, enclosed rotating drum, so smells stay down better than open piles. The trade-off is batch size, plus the plastic drum brings an axis cracking risk over time, so plan for careful loading and handling.
Who it's for: People composting near doors, patios, or windows, who accept smaller loads. You want quieter, cleaner handling and better smell control, even if the drum needs extra care as it ages.
Who should skip it: Households with lots of kitchen waste and yard scraps, or buyers who want long-term drum durability without an axis cracking concern. A larger-capacity system will waste less of your time.
In-Depth Review
Performance
The Mantis Back Porch 35 gal focuses on controlled breakdown rather than sheer volume. With a compost capacity of 35 gal and an overall size of 37 x 31 x 26 in, you get a true tumbler rhythm. The rotating drum design helps move material through the batch. That matters because good airflow and mix reduce dry pockets and soggy spots.
In the Performance pillar, this model scores 7.4. That lands in the “Reliable heat and airflow” range for a tumbling system, not in the top tier for “Fast, odor-free composting.” The reason is simple: a 35 gal drum can do clean work, but it has less thermal mass than larger units. You can still expect low odor and steadier decomposition with regular turning, but you should not treat it like a large, fast reactor for heavy loads.
Two build choices support that day to day performance. The drum uses double wall, high density polyethylene with an insulating air cell, and the end caps are BPA-free, food grade plastic. Paired with its pest-contained design, the closed approach helps keep smells in check while you rotate. That aligns with the Best for Low Odor role, even if decomposition speed will vary with how wet your inputs are.
Build Quality
Build quality is one of the clearer strengths here. The frame material is steel, described as polyester powder-coated black steel tubing. That matters for porch use, where the unit sits through humidity swings and periodic wet weather. The unit also weighs 38 lb, which generally helps reduce the wobble that plagues lighter tumblers once you load scraps in.
This earns a 7.6 in the Build Quality pillar. In the scoring language, that maps to “Sturdy frame, smooth bearings” as the closest match. The honest caveat is in the drum. Your specs list the drum material as plastic. And the review’s cons include an “Axis cracking risk,” which points to a common failure mode at the rotation interface when plastic takes repeated stress over time.
You feel that trade-off in how you should use it. A plastic drum can keep weight down and resist some corrosion, but it also means you need to be mindful about load balance. Overloading or turning with lopsided material can add strain at the axis. If you rotate regularly and avoid uneven packing, you are doing the right thing for longevity, especially given the stated cracking concern.
Ease of Use
Turning and unloading are where tumblers justify their space. This model uses an assembly-required rotating tumbler design, and it comes in at 35 gal capacity in a compact footprint of 37 x 31 x 26 in. The smaller footprint helps for porch storage, but it also sets expectations for how much you can process per batch.
In the Ease of Use pillar, the score is 7.8, which fits “Smooth rotation, simple cleanup” for most buyers who actually use the turning schedule. The unit’s closed container approach supports odor control, and that same layout typically makes it easier to manage mess than an open bin. It also encourages more consistent mixing because you have a reason to turn it often.
The snag is initial setup. Assembly required is listed as Yes, which means you should plan time and follow the provided assembly instructions. Those instructions exist as a separate document for the Back Porch ComposTumbler. Add another practical factor: because the drum is 38 lb overall, you can move it when needed, but you still want to keep it stable while you load and rotate. Smooth use depends on stable placement, especially with a plastic drum and the “Axis cracking risk” noted in the cons.
Value
Value is a weighted mix of function and durability. Here, the Mantis Back Porch 35 gal lands at 7.6. That corresponds to “Great results for the price” in the template mapping. The unit’s strongest case is not speed bragging. It is odor control and pest containment in a closed system, plus a steel frame to keep the drum stable while you work.
Still, value can wobble if your expectations do not match the numbers. The compost volume is 35 gal, and one of the cons calls out “Low compost volume.” If your household generates a lot of kitchen scraps, you will run more batches than you would with a larger tumbler. The drum is also plastic, and the cons mention “Less durable plastic drum,” so you should expect wear points to be a longer-term consideration.
For the “worth it” buyer, the specs point toward a focused use case: a compact tumbler that sits near living space. With overall dimensions of 37 x 31 x 26 in and a steel frame, it is easier to place than bulky systems. And with a 35 gal capacity, it is sized for steady, smaller batches rather than peak yard dump days.
Frequently Asked Questions
How much compost does the Mantis Back Porch 35 gal tumbler hold?
The Mantis tumbler is rated for 35 gal compost capacity. Keep in mind that your finished batch volume depends on how much you add and how dry your inputs are. Overfilling can slow airflow and mixing.
What are the overall dimensions and weight of this compost tumbler?
It measures 37 x 31 x 26 in and weighs 38 lb. If you plan to move it often, think about that weight plus the load from full compost. Check the space on your back porch or patio for clearance around the door and rotation.
Does this compost tumbler need to be assembled, and how hard is it to set up?
Yes, assembly is required. Expect to assemble the steel frame and install the drum for rotation. Plan on following the instructions carefully so the drum sits aligned; misalignment can make turning harder.
What materials is the Mantis Back Porch 35 gal compost tumbler made from?
The frame is steel and the drum is plastic. The steel frame should feel stable, but the plastic drum is the part you handle most during turning, so it can be a wear point over time. Place it where it will not get struck or bumped during use.
Is the low odor composting design enough to use it near doors or windows?
This tumbler uses a pest-contained design and is built to help keep odor down. Still, odor depends on your input balance and moisture level, not only the container. If you add mostly wet scraps, the contents can smell even with good containment.
What is the axis cracking risk on this tumbler and how can I prevent it?
The main durability concern is axis cracking risk. To lower the odds, avoid forcing the drum to turn when the contents are packed or too wet, and do not start with a completely full batch. If you notice unusual resistance or wobbling, stop and check alignment before continuing.
Final Verdict
The Mantis Back Porch 35 gal Compost Tumbler is a recommended buy if your top goal is low odor and pest control on a small porch or yard. Its pest-contained design helps keep smells down. Still, the compost volume feels limited, and the plastic drum can be less durable. It turns cleanly enough for routine use, but it may not satisfy gardeners chasing large batch output.
If you want quiet, contained composting rather than high throughput, this tumbler fits well. It is a solid choice for steady, low-smell backyard composting.