Q: I have seen a picture with a clear pipe on top of the rock but cannot find the pipe in my aquarium.
A: The original aquarium design included a clear pipe, however this was difficult to keep clean and algae free. As it wasn’t essential to the design we've removed the pipe, so the newer version do not have a pipe. We believe the design looks better and it means you don’t have to worry about keeping the pipe clean.
Q: The air pump is plugged in & vibrating, but there aren’t any bubbles in the aquarium.
A: There is a one way valve which prevents water coming down the tube if the power is switched off. You can see this valve in the airline (the tube running between the air pump and the aquarium), check that it is pointing in the right direction – the small part should be facing the air pump. If you aquarium has been running for a while the air stone may have become blocked with dirt or lime scale, this is easy to replace with a new one.
Deco O Mini aquariums also have an air regulator, check that this is not completely shut by turning the dial.