# OsAtNb Quiet 4in1 Internal Aquarium Filter, 500 L/H

Source: https://www.ranked10.co.uk/pet-supplies/best-aquarium-filter/osatnb-4in1
Ranked #10 in "Best Aquarium Filter 2026: Turnover Is the Only Number": https://www.ranked10.co.uk/pet-supplies/best-aquarium-filter

- Price: £19.99 (checked on Amazon UK on 2026-09-11)
- Amazon rating: 3.8 from 888 ratings
- Buy on Amazon: https://www.amazon.co.uk/dp/B094H12D2Z?tag=ranked10-21

The OsAtNb 4-in-1 is a 500 L/H internal filter for £19.99, with 3.8 stars from 888 ratings and 20 per cent one-star — one in five buyers.

It takes tenth because its listing is internally inconsistent in three ways, and because a fifth of its owners giving it one star is a record rather than a complaint. The specification looks good and the reviews do not agree.

## Specification

| Field | Value |
|---|---|
| Ratings | 3.8 from 888 |
| Tank range | 200L in the title, 180L in a bullet |
| Wattage | 6 W labelled as horsepower |
| Maximum flow | 500 litres per hour |
| Outlets | Three types |
| Price | £19.99 |

## Questions people ask

**Why is it last?**

One in five of its 888 ratings is one-star, which is 178 buyers, and the listing contradicts itself on tank size and units.

**Is the horsepower rating real?**

No: the field is labelled horsepower and contains 6 watts, which is 0.008 horsepower.

**What tank size is it for?**

The title says 20 to 200 litres and a bullet says 20 to 180. At 200 litres, 500 L/H is 2.5 turnovers an hour, below the recommended range.

**Does it work?**

Plenty of reviewers say it is powerful and quiet; the concern is how long it lasts, which is what the one-star comments describe.

**Why not buy it anyway?**

For £4 more the NICREW Magi700 publishes a coherent flow and tank range, a spare impeller and a one-year warranty.

**How many ratings does it have?**

888 at the time of collection, averaging 3.8 stars, with 57 per cent five-star and 20 per cent one-star.