JBL Check valve for air
Backflow stop for air pumps

  • Protects devices such as diaphragm pumps against backflow of aquarium water
  • Easy to install: insert the backflow stop between air pump and air stone or other air-operated accessories with the arrow pointing towards the aquarium
  • For air hoses 4/6 mm in diameter
  • Accessory for air hoses, diaphragm pumps and air-operated accessories: special water backflow stop
  • Package contents: 1 backflow stop for air pumps with air connection 4/6 mm
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Product information

All air pumps need to be protected against back-flowing water. For this reason the JBL backflow stop has been developed. This “check valve” just needs to be integrated into the air carrying hose. The arrow on the backflow stop indicates the mounting direction. It needs to pointing away from the air pump.
Tip: install the backflow stop as close as possible to the water surface to stop a possible backflow in good time. Note: check valves for air do not work with CO2! These check valves are also unsuitable for air pipes because the air pressure of the air pumps is not high enough to open the CO2 check valves.


JBL check valve for air, 4/6 mm

Art. no.:
EAN Code:
For Ø:
4/6 mm
Volume packaging:
0.170 l
Gross weight:
10.000 g
Net weight:
3 g
Weight factor:
15/160/135 mm

Technical Data

Is my SafeStop damaged if I can’t blow through it?

The retaining spring in the check valve fits very tightly and ensures that no water can return. Therefore the air pressure of a diaphragm pump or our breath is not strong enough to open the spring. The valve can be opened by the pressure of the ProFlora bioCO2 systems and also the m and u series. Check valves used in air systems have a smaller counter-pressure and are also part of the JBL range.

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safety instructions

  • safety instruction for accessories
    17 kByte