Mulm In The Filter

[maurizio]

I have a 8-month old low-end brackish tank, fishless cycled for a couple of months in autumn last year. The filter is a Eheim professionel 3 350.

I did a first light filter cleaning early this year, when I simply quickly rinsed the two sponges in the siphoned water, and noticed a lot of brown mulm floating in the filter water. Unsure it was the good bacteria, I let it stay. However, when I restarted the filter a huge amoungt of this stuff ended up in the tank, just after I had changed the water! So, now that I cleaned the tank again, I've been more thorough, squeezed the sponges more, and removed ALL the water I had in the filter, including as much mulm as possible. Now, apart from the outcome of having a small (0.1 mg/l) NO2 spike, clearly indicating that I did exaggerate, when I restarted the filter I still had a burst of mulm ending up in the tank!! It turned so dirty I could hardly see through!

What's wrong in what I am doing? How to avoid the (beneficial?) mulm ending uo in the tank???

Thanks!

 

[Comacchio]

Try cleaning out the intake and output tubes for your filter.

 

[CezzaXV]

This always happens whenever I do anything inside my filter. It generally clears itself up pretty quickly.

 

[maurizio]

Try cleaning out the intake and output tubes for your filter.

Cheers, Comacchio,
I thought of that, but, if the problem is in there, why don't I see mulm coming in all the time??! It strictly happens after I cleaned the filter. Also, it doesn't happen if I stop the filter and then restart it, so I believe it's not even connected with any initial burst in pressure the filter may exert inside the pipes at start-up...


Thanks Chezza,
indeed it clears up (in the sense that it simply settles on the substrate!!) soon, I just can't stand that, after a nice water change, I have that mess coming in in bursts!! But if it's the way it should be, fine. I'm just afraid of doing something wrong, being a beginner...

 

[maurizio]

The question however remain...: should I, or should I NOT, remove all the water from the filter?? Is the mulm a good (bacteria) or a bad thing?

 

[CezzaXV]

You shouldn't need to clean the filter very often. My tank has been running with fish since November (and was cycling since September) and I've not once had to clean the filter. You only need to clean the filter if you notice the flow dropping considerably; it's not something you need to do with every water change. For the most part you can afford to leave the filter alone.

 

[Gilli]

It always happens to me too - ive solved the problem by holding my net over the outflow to catch all the crud when I turn the filter back on until it runs clear!

 

[OldMan47]

I dump as much of the water in my filter as I can during a cleaning, then I use tap water to remove anything left behind in the filter casing. The filter media is treated completely differently though. That media just gets a good rinsing in old tank water. We try to keep as much as practical of the beneficial bacteria in the media but the functional pumping parts of a filter need to be kept very clean in order to work properly.

 

[maurizio]

Many thanks to you all, Fish-People! That's all I needed to know!

Gilli, great idea, I'm going to do that!

Cheers, Maurizio

 

[ZoddyZod]

Mulm will ALWAYS shoot out of the filter after a good clean. It has been stuck in there according to the flow of the water through the equipment. Cleaning the filter dislodges it and provides it with the poetntial to 'escape'.

You can minimize it with some of the tips above, but I'd be very surprised if you eliminate the ejection completely after a clean.