Rather than fork out for a whole new manifold, you could try buying a 3/8" UNF 90 Degree elbow (about £14 3/8 90 Degree elbow by: Sub Aqua Products - DiveLife - DiveLife, ).

You can plug it into to orifice at the end of the standard manifold. It will get your hose in the right direction......The L is on a swivel so it means it is easy to screw in your additional hose without taking the manifold off the box.

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