Reef tank and cannister filter

[Jamba]

Hi all

I have a 30 g reef tank. I just read an opinion that says "don't use a canister aquarium filter for a reef tank unless you plan to clean the filter daily."

http://www.marineandreef.com/shoppro/filters_chart.html

I have a Ehiem cannister filter that is running on the system. Does anyone know why they recommend against this?

Thanks,
J

 

[nunofs]

A canister filter with either mechanical or biological filtration media (ie, filter floss or bio-balls) will tend to generate nitrates, due to accumulation of detritus and their processing by nitrifying bacteria. That's the reason why they're not recommended for use on a reef tank, where the biological filtration is done by live rock.

Nuno

 

[Jamba]

Eheim cannister on reef

Thanks for your reply.

As for nitrates, my tank registers at zero.

The cannister does not have bio balls, or filter floss. It contains mechanical filteration and nitrifying bacteria substrate.

I have cleaned the Eheim cannister filter once ever three months. The first time I cleaned it I was quite surprised at the lack of debris. Usually it was full of stuff when I had a freshwater tank. I assumed the protein skimmer cleaned most of the gunk, and the live rock lessened the load on the cannister.

The last time I cleaned the cannister, it was acting as a refugium of sorts. I found a lot of baby shrimp (either that or copepods). Kind of cool.

Cheers,
J

 

[nunofs]

As for nitrates, my tank registers at zero.

That's a good sign, means you're doing an appropriate level of cleaning/maintenance on the canister. So I'd say you have nothing to worry about... but if you ever see nitrates climbing, then suspect the canister.

The cannister does not have bio balls, or filter floss. It contains mechanical filteration and nitrifying bacteria substrate.

I mentioned those kinds of media as examples... bio-balls are a "nitrifying bacteria substrate".

Nuno