Wear on the impeller - When should I replace it?
There is no general answer to this question. As with a car tyre, the duration and intensity of use is decisive. Many customers use the impellers for several years without any noticeable change. Heavy use of the impeller results in a shorter service life. With a car, you know the wear and tear caused by heavy braking, mechanical damage and many kilometres driven.
The following factors apply to an impeller:
1. Running time in hours
2. Throttling of the flow rate (max. 50 %) and thus lower cooling capacity
3. Dry running during water change (see 2.)
4. Mechanical damage (e.g. by snails, improper installation after removal, ...)
5. Heavy soiling
As it is a wearing part, the impeller is not covered by the warranty. For a long service life, you need to clean it regularly. This will prevent increased running noises. The impeller housing, the impeller and the shaft can be cleaned with a suitable cleaning brush.
If it is necessary to replace the impeller due to wear, always replace the complete set, impeller with shaft and 2 rubber bearings. This is the only way to ensure proper functioning and smooth running. When removing the impeller and shaft, a rubber bearing often gets stuck at the bottom of the impeller housing and is very difficult to remove. JBL has developed its own special tool for this purpose, which is available from pet shops under the name "Pulling aid for impeller bearing". A useful cleaning brush for the impeller housing is also included in the tool.
The filter / pump hums during operation
It’s to investigate the cause of this. With pumps and filters positioned inside, you do not need to do anything other than hold the unit freely in the water, keeping it out of contact from any other objects. It is important that the unit remains completely under water and is only touching your hand. If the running noise is now quiet, there is no sign of wear on the rotor, it is just resonance transmission to surrounding elements such as the cover, the base cabinet or anything adjacent to the aquarium. You can then decouple this by making small adjustments.
For external filters, make sure that the filter has 4 rubber feet at the bottom (except for the model CPe1901/2 with castors) and that it is only touching the cabinet there. To test the filter, place it next to or in front of the aquarium on a soft surface (e.g. a thick towel) and make sure that the hoses are not in contact with the cabinet. Many aquarium cabinets act like the sound box of a guitar with its sound hole. The smallest noise is amplified by the hollow body. Therefore, a soft underlay and, if necessary, lateral insulation are advantageous if the resonance is to be amplified. Tubes lying on top or in a very rigid installation with further attachments lead to the same effect. The test with the filter outside the cabinet, as described above, provides information about the actual operating noise.
Strong running noises are caused by a worn impeller, a too strong load on the impeller due to a power reduction (dirt or throttling) and by a too small height difference between the water surface and the filter head, as described in the manual. Another possibility is that CO2 sucked in from the fertiliser system or air from the diaphragm pump, which are introduced near the filter, cause loud running noises.
Why is the suction cup on my internal filter red-brown or light grey?
For the CristalProfi greenline internal filters, "red-brown" and "light grey" suction cups were used for a time. They are fully functional and differ only in their colour. In the spare parts shop you will find the black suction cups which were unavailable for a while, should you not like the colour.
My filter has become loud after a few months. What’s the reason for that?
The impeller of the filter is subject to constant wear and tear. We recommend you replace it. This way its smooth running is ensured. Make sure that the noises are not caused by trapped air.
The guarantee covers defects in material and assembly. The guarantee does not cover parts subject to wear and tear, such as the impellers or shafts as well as damage caused by external influences and improper handling.
How do I attach the suction cup to the CristalProfi greenline internal filter?
Press the enclosed large suction cups with a turning movement and gentle pressure into the side openings of the pump head. Make sure that the central pin reaches into the hole in the suction cup and reappears when it is attached. The correct installation is indicated in the following figure.