Silicone Rubber Hose Food Grade Tube Pipe Fish Car Aquariums Air - Black Multi

Match the hose ID to the barb diameter on your air pump outlet and air stone inlet. Most standard aquarium air pumps use a 4 mm (approx. 5/32 in) barb, so the 4 mm × 6 mm or 4 mm × 7 mm variants are the most common fit. If your fittings are metric, measure the barb OD with calipers and select the hose ID that is 0.5–1 mm smaller for a secure push-fit seal.

Yes. The hose is made from food-grade silicone rubber, which does not contain BPA, phthalates, or other plasticisers that can leach into liquids. It is odour-free and tasteless, making it suitable for homebrew beer and wine lines, drinking water transfer, and aquarium use where fish health depends on water quality.

Silicone rubber is rated to approximately +200 °C (+392 °F) continuous service, which covers typical engine coolant temperatures of 80–110 °C. It is commonly used for heater bypass lines, coolant overflow routing, and vacuum hose replacements where standard rubber has cracked or hardened. Confirm the specific temperature rating for your application before installation in high-pressure coolant circuits.

Silicone rubber has a lower modulus than standard PVC tubing, so it resists kinking better at moderate bend radii. For very tight bends — smaller than approximately 3× the outer diameter — use an elbow barb fitting instead of forcing a sharp bend in the hose. This maintains full flow and prevents stress cracking at the bend point over time.

Use sharp scissors or a fresh utility knife blade and cut in a single clean stroke rather than sawing. Silicone is soft enough that a dull blade will compress and deform the end rather than cutting cleanly. After cutting, check that the end face is square — a slight angle can cause the hose to seat unevenly on a barb and leak under pressure.

Black silicone contains carbon black pigment, which acts as a UV absorber and generally improves outdoor UV resistance compared to clear or translucent silicone. This makes the black hose a better choice for any routing that is exposed to sunlight, such as outdoor pond air lines or engine bay applications where the hose is visible through the bonnet gap.

Standard worm-drive stainless steel hose clamps work well for pressurised connections. For low-pressure aquarium and air lines, a push-fit barb fitting with the barb OD approximately 0.5–1 mm larger than the hose ID creates a reliable seal without a clamp. Avoid over-tightening clamps on silicone — the material compresses easily, and excessive clamp force can cut into the wall rather than sealing it.