Most likely, this is caused as a result of the impeller being 'starved' of water.ДЎst : broken impeller or impeller shaft, check and replace if necessaryДўnd, check your strainer on the intake - is it all blocked up? Yes - clear the strainer see if that helps.ДЈrd, and most likely, clogged tubes and pipes. I recommend doing this anyway, so you learn what the sound of restricted flow sounds like If the rattling gets worse (louder), then there is most likely something blocking and/or inhibiting the flow on one or both water paths. What I suggest you do is first - with the power still on, turn off (or partly turn off) one of the taps. A 'rattling' sound - it sounds almost like the little impeller inside is banging against the sides. Secondly, it could be a sign of a fatiguing o-ring, or a small air leak from one of the connections.Дў. The most obvious cause is during maintanence and allowing air into the system. This can be alleviated by gently rotating the canister on its sides until all the air is expelled.Д®DIT 2019: If the water rushing sound is sporadic, it could also be a blocked intake strainer and/or a exhausted(clogged) fine filter sponge.Д¬heck and clean strainer, and/or replace fine filter pad and see if that helps.

Water Rushing sounds - normally indicates the presence of air in the system. The Eheim Classic filters are super silent, and in my experience, there are two types of noises made by the Eheim Classic.ДЎ. If you require carbon in your filter, I suggest placing it on top of the white filter floss (it also makes it easier to remove ) (Note: the descriptions on the right are in the reverse order to how it appears in the canister - pay attention to the numbers, you can't go wrong) Д¬arbon in the Classic - Carbon is generally considered un-necessary unless you are trying to clear odours, discolourations or medicines. The below shows (what I believe) the most efficient layout of media in the Classics. So how should you consider this when deciding on media layout, well the first thing you want to happen is for the water to be pre-filtered, then mechanical, then biological, then polished, and finally chemical (if required).ДЇor more info: 3 Stages of Filtration and What They Do. The Eheim canisters work on a bottom to top system - this means that the water enters the bottom and travels up the filter and returns to the aquarium. It can restrict the flow of water, ultimately over-heating the motor. Note: Whilst you can turn the taps down, I do not recommend this approach. This is similar to the effect of putting your finger over the end of a hose, the smaller you make the hole, the greater the pressure it comes out, as you release your finger, the pressure is much less. If you find your filter is producing too strong a current, the best advice is to take the spray bar and drill the holes wider.

Note: pay attention to the hMax rating, this is the total height that the filter can return water to (generally 1.5m, or 5ft) With gravity in mind, the canister must be located below the aquarium to ensure optimum siphon effects. The filter relies on gravity to feed the water to the canister, contrary to popular belief, the pump/impeller does not suck water out of the tank persay, it only forces it back up the tube. Splashing does not help, and can upset some of the more peaceful species. Note: it is only necessary to have the surface moving/rippling to conduct gas exchange. I position it there so that with evaporation, I don't get splashing, maintaining a more silent tank. There is no need to have it 'splashing' water back. The spray bar is positioned about 5cm (2') below the water surface, and is angled toward the surface, just enough to create movement on the surface. Mine is positioned across the back of the aquarium, and sprays water from the back to the front. I would also consider putting some cut up, brand new, never seen detergent panty hose over the strainer to stop sand from entering.

If I had a sand substrate, I would raise this to 2.5/3cm (1-1.5') above the sand to reduce the chances of sand entering the filter and damaging it. I position mine with the bottom of the strainer about 1.5cm (0.5'-0.75') above the substrate. Note: the intake tube connects to the bottom connection on the canister So my philosophy on water filtration is as follows: Water enters the tank from the top and travels around the aquarium, then gets sucked back into the filter from the bottom, therefore: I've had a search of the forums, and there are similar topics, but I figured with the popularity of these filters, I'd share my tips and tricks of using one ( 2213, but applies to all Classic filters) and the things I've learned.

Eheim 2260 filter