Pawfly Aquarium Air Stone, 2 pack, 5 inch, cylindrical

Two gray plastic cylinders come in this pack, each one 5.1 in long and 1.15 in across. The Pawfly aquarium air stone is listed for fish tanks, DWC systems and small ponds, and its many micro holes release dense, even bubbles. Each cylinder carries a square holder at either end and weighs 6.16 oz on its own.

What do owners say about these air stones?

Several reviewers report that air comes out mainly at one end of the cylinder, while others mention that the stone stays in place in the water. Two reviewers describe it as fragile and breaking when dropped, and a further two note that the connection end was not sealed properly.

Checks before you buy

Your pump needs more than 5 W of power to match the stone's stated 16 L/min jetting volume, and the airline tubing should have a 3/16 in or 3/8 in inside diameter to fit the connection. Factor in the footprint of each cylinder, 5.1 in long and 1.15 in across, in the tank, DWC system or small pond where it will sit. Both stones together weigh 175 g, and since some reviewers describe the plastic body as fragile, handle it with care when you move it.

Cylinder shape and bubble output

The stone is a plastic cylinder made for continual bubbling. Its many micro holes release dense, even bubbles, and the jetting volume is 16 L/min.

• The cylinder measures 1.15 in in diameter and 5.1 in in length.
• A square holder sits at each end of the stone.
• Two cylinders are included in the pack.

What the pack holds

• 2 cylindrical aquarium air stones, gray plastic
• 1 square holder at each end of every stone

Before first use, water should cover the whole stone for an hour of soaking. Once clogging sets in after weeks or months, a brush used regularly keeps it clear.

Questions buyers ask

How long is each air stone?

Each cylinder is 5.1 in long and 1.15 in in diameter.

How many air stones come in the pack?

The pack contains 2 air stones.

What size airline tubing fits the stone?

The stone connects to standard airline tubing with a 3/16 in or 3/8 in inside diameter.

What pump power does the stone need?

The manufacturer recommends a pump rated at more than 5 W.

How should the stone be prepared before use?

Before first use, water should cover the whole stone for an hour of soaking.

What customers say

Customers find the air stone performs well, with one mentioning it works great for adding circulation to ponds, and they appreciate its quality, with one noting it's suitable for both aquariums and hydroponics. The airflow and bubble production receive mixed feedback - while some praise the even bubbles, others report bubbles only coming from one side. Customers find it heavy and expensive, and durability is a concern as customers report it can break if not handled carefully.