What System Of Filtration Would Be Best?

[firetank]

I think a good simile is the filtration used on large koi ponds;

generally you have MORE biological surface area (as in vortex systems) but the water passes through relatively slowly to give the water greater contact
with the media.

If you fire the water through too quickly the biological filtration is less effective....

 

[Ferris]

The flow rates given on Ehiem filters are the actual figures from where the filter is running with new media, obviously this will slow as the media gets dirtier but with regular maintainance the figure should stay pretty close to what it says

That's good to know - typical Eheim and a shame others don't follow suit.

You can't really compare algea eating mbuna to carnivorous Cichlids like Oscars which have a high protein diet, the type of waste they produce is vastly different, a better comparison would be to compare them to common plecs which have a similar dietry requirement. Vegetarian fish produce nothing like the waste of predatory fish in terms of how much ammonia it contains.

I much prefer the Plec comparison - my Plecs create far more waste than my Oscar anyway.

If you need more mechanical filtration then fill the last stage of the filters with filter wool, if you set up a canister properly with Bio Mechanical-Biological-Fine Mechanical with the media in that order it will trap anything that goes through it. I can see what you are getting at, that in order for the soild waste to be picked up by the filters you need a strong flow to lift it off the substrate, but this faster cycling of the water through the filters isn't improving the actual filtration, all its doing is costing more to run to get the same effect. If extra flow really is needed it would be better to add a well positioned powerhead which is cheaper to run since it doesn't have to push water a meter up a tube and so has a smaller lower wattage motor, and costs less than £30 to buy rather than at least double that for another large canister filter.

Not really concerned about flow - quite the opposite, it's not important for Mbuna tanks provided the surface is sufficiently agitated. The high turnover is simply about passing the water etc through the filter as often as possible to keep on top of the constant waste production in heavily overstocked Mbuna tanks.

 

[darrel69]

It seems people (everywere on the net) have different views/opinions about filration, i guess you should just do what you think's right, and adjust as you think's necessary. If you think your water's not being cleaned/filtered enougth, then up it.

I personally believe the more times your water is filtered per hour, the cleaner it will be for your fish. There's no way i would go below 6x for any tank at all, and i think over 14x is a little OTT. 6x for juvies - 14x for really overstocked mbuna adults.

The Eheim Classic 2217 is rated for tanks up to 600 litres and has a turn over of 1000 lph, do you really think that a company with the reputation of Eheim would get it so wrong?

But Eheim dont know what fish your going to keep do they, my guess is that they've rated them for "standard" tropicals like Neons, guppies and what'not... IMO most Cichlids would need alot more filtration than 1.5x.

Also, the number of times ive read "You cant over-do filtration" everywere i look, but you say a 10x turnover would be no cleaner than a 3x, so in your opinion you can over-do it ?? because there's no point, it wont be any cleaner... ??

 

[CFC]

I absolutely agree that 1.5x per hour would be no where near enough for even a moderately stocked tank, thats why i earlier said i would recomend using two 2217s for 2000lph on a 350L tank giving nearly 4x per hour, if 2 large canisters rated for 1200 litres between them on a medium sized 4 foot tank isnt enough filtration for what you are putting in it, mbuna or not, then you really need to have a good think about whether the tank is even big enough in the first place.

 

[Ferris]

if 2 large canisters rated for 1200 litres between them on a medium sized 4 foot tank isnt enough filtration for what you are putting in it, mbuna or not

Completely agree with that - 2 1200LPH filters should be more than enough on a 4 foot tank for Mbuna whether it's a 55 gal, 70 gal or 90 gal.