This review dives into the Marineland Penguin 350 Power Filter, examining whether it's a worthwhile upgrade or an overpriced replacement for its predecessor. The author's experience begins with a decade-old model experiencing impeller issues, prompting a costly repair contemplation. This leads to purchasing the new Penguin 350, a seemingly affordable solution at around $25. The review focuses on a comparative analysis, highlighting both the improvements and shortcomings of the newer model against the older, more durable version. Key areas of comparison include build quality, filter media capacity, bio-wheel size, and noise levels.The analysis delves into the specifics of assembly, filter media options, and the impact of the larger filter compartment. Ultimately, the review explores the value proposition of upgrading to the newer model, weighing the benefits of increased filtration capacity and ease of maintenance against the perceived drop in overall build quality and durability. The conclusion offers a balanced perspective, providing readers with the information needed to determine if the Marineland Penguin 350 is the right filter for their aquarium needs.
Pros And Cons
- Larger filter compartment for media
- Quieter than the older model (with splash guard)
- Larger bio wheels with more surface area for biological bacteria
- Cheaper plastic construction than the older model
- Can be noisy without splash guard
- Splash guard may still allow some splashing
- May require higher water level to prevent trickling noise
Read more: 5 Amazing 3-Stage Aquarium Sponge Filters
The Problem with the Old Penguin 350
My old Marineland Penguin 350, over a decade old, started exhibiting issues. Sand from my saltwater aquarium apparently entered the impeller housing, causing a significant rattling noise. Replacing the impellers proved costly, around $20-$25 after shipping.

This prompted me to explore the newest model as a potential solution. The high cost of impeller replacements made upgrading a more attractive option than repairing my aging filter.

Unboxing the New Marineland Penguin 350
The new filter arrived, priced at approximately $25 on Amazon. The packaging boasts 'MarineLand Bio-Wheel Penguin 350 Power Filter,' emphasizing multi-stage filtration and bio-wheel technology for efficient toxin removal.

It's designed for aquariums up to 75 gallons, with a 350 gallons-per-hour filtration rate. However, I chose not to use the included filter cartridges, opting instead for a custom filter media setup as detailed in a previous video.

Filter Media and Setup
The included filter sponge is sizable (17x17 inches, 2 inches thick), easily cut to fit various filter housings. It provides both mechanical and biological filtration.

The box contains the bio-wheel, cartridge, filter cover, and adjustable mid-level intake. It also offers chemical filtration using carbon, although I don't typically use carbon unless addressing specific water chemistry issues.

Comparing Old vs. New Penguin 350
The new filter's plastic feels significantly cheaper than the older model; the older model's plastic is thicker and more durable.

The new model features a larger filter media compartment and a built-in diffuser to potentially reduce noise. The overall construction is simpler.

Assembly and Filter Modification
Assembly is straightforward; the impeller is easily accessible for cleaning. I chose to use my sponge filter modification from the previous video, which is more compatible with the larger filter media compartment.

The larger filter compartment is a significant improvement; the old filter required a divider to prevent filter media from interfering with the bio-wheel. The new bio-wheels are significantly larger, offering more surface area for beneficial bacteria.

Final Thoughts and Conclusion
The Marineland Penguin 350 is a decent filter with improved media storage over its predecessor. The larger bio-wheels offer increased biological filtration. However, the build quality feels noticeably cheaper.

While the larger media compartment and improved bio-wheels are beneficial, the less durable plastic is a concern. Consider this filter if you need a larger filter compartment or have issues with your old model, but be aware of the potential drawbacks in build quality. Priming is essential to avoid burning out the impeller.

The noise level is moderate, but the splash guard helps reduce it somewhat. Keeping a slightly higher water level also helps minimize noise. Overall, it's a functional upgrade, but not necessarily a superior product in terms of build quality.