MCE300 changes in water level

Dear Mr McMahon

I think the problem maybe due to a partial blockage in either the air tap or more likely the air venturi.

The air venturi is the small hard pipe that sticks out of the pump suction side to which the soft air pipe

pushes onto.

As air meets water at the venturi hard calcium carbonate and salts can build up inside it. Cleaning the

inside of the pump doesn't tend to shift it. If the air becomes partially blocked at this point the ratio of

air to water slowly drops, this equates to a lack of air volume in the skimmer body and a drop in level.

I would advise that you remove the pump and venturi, pull the soft pipe from the venturi and run a drill

bit(by hand) through the venturi that is just smaller than the inner diameter of the pipe.

This should clear out the venturi of any hard calcified build up. I also find that warming up a cup of RO water

(not boiling as it will distort the plastics) and allowing the air line to pull the water in from the cup by dropping

the air tap into the cup can help keep the venturi clean if done on a weekly basis.

Also remove the air tap, open the valve and blow through it in reverse to remove any dust build up from it.

Also make sure that the water level at the suction pipe isn't too low as the pump will have trouble pulling

water from the aquarium. Levels can drop if the aquarium isn't kept top up and the water level drops due to

evaporation.

Hope this helps

Tony