Pawfly Aquarium Air Stones, 4-Inch ASR-100 Diffusers, 2-Pack

Pawfly Aquarium Air Stones are a two-piece air diffuser set for aerating aquariums, fish tanks, ponds, buckets, and DWC reservoirs with dense medium bubbles.

• ASR-100 model with a 15 L/min jetting volume — adds a steady stream of bubbles to water.
• Recommended for an air pump over 4 W — match the pump to the diffuser’s stated power requirement.
• Fits standard ID airline tubing in 3/16 in (4.76 mm) or 3/8 in (9.53 mm) sizes — supports two listed tubing sizes.
• Mineral material sintered at high temperature — made for aquatic setups without affecting aquatic health.
• Measures 4 in diameter x 1.5 in high (10.16 cm diameter x 3.81 cm high) and weighs 11.6 oz (329 g) — the wide, flat base sits stably in the tank.
• Dense medium bubbles — help increase oxygen solubility in the water.

Water aeration is useful in fish tanks and aquariums, as well as ponds and hydroponic DWC reservoirs. These Pawfly air stones are made to diffuse air from a connected pump into the water, making them a practical choice when you want bubble-based aeration in a contained aquatic or growing setup. The two-piece set provides a diffuser for each of two setups or a pair for one arrangement.

What do these Pawfly air stones do?

They release medium-sized bubbles to aerate water in fish tanks, aquariums, ponds, and DWC reservoirs. The bubbles are designed to increase oxygen solubility in the water, supporting the aeration needs of aquatic environments and plant-root systems. Their mineral construction is sintered at high temperature, and the material is made for use without affecting aquatic health.

• Use in aquariums, fish tanks, ponds, or DWC systems.
• The set contains two air stones.

What pump and airline tubing fit?

Use an air pump rated above 4 W and connect standard ID airline tubing in either of the two stated sizes. The model is ASR-100, with a jetting volume of 15 L/min. Match your pump and tubing to these requirements when setting up the diffuser.

• Recommended air pump power: over 4 W.
• Airline tubing options: 3/16 in or 3/8 in inner diameter.

How do I prepare and maintain the air stone?

Soak the air stone completely underwater for more than three hours before using it. Brush it regularly to clear buildup; after weeks or months of use, the pores can become clogged. The wide, flat base helps the diffuser remain seated in the tank while it produces bubbles.

• Fully submerge before first use and soak for more than three hours.
• Clean with a brush regularly as use continues.

This two-piece set suits aquarium and pond keepers, as well as DWC growers, who want a mineral air diffuser for a pump-powered setup. It is sized for placement in water reservoirs, with a broad flat base designed to sit stably rather than float. Pawfly combines two air stones with stated pump and tubing requirements for straightforward selection across these uses.