Eheim Vs Fluval Canisters

[Atsy]

I got the Fluval 406.  Works great so far!  Found it for about $30 less on Amazon than the LFS and Petco / Petsmart.

 

[snazy]

The recommendation of 10x the tank volume an hour for planted tanks takes into consideration that the manufacturer's rating true flow is actually less. So for a 50G tank, get a filter rated 500G/H.
As for blowing away your fish, I doubt it 10x flow will blow away anything, unless you intend to keep fish like bettas or similar. Most filters now have an option of reducing the flow. I suppose Eheim filters would at least if you really wish to decrease it, but I doubt it you'll need to.
It may sound much to some but actually it is an average flow. Some folks run way higher than that in planted tanks.
If I have to decide between a Fluval and Eheim, I'd go for the Eheim.

 

[Zikofski]

yes, also if your filter dose not have the ability to reduce the flow eheim do inline taps or stoppers that will also reduce the flow this is what i plan to do with my filter as it is ridiculously over powered for my new tank but i rather have the flow restricted than not enough
 
and @ raptorrex
 
i diss agree with changing the media inside the filter can alter the way the filter works in a bad way and could be both good or bad, it all depends on the user, for example my old filters have carbon now from my research carbon is good but not needed and after a few weeks to a month dose not do its primary job and needs to be replaced for the users that don't have the ability or the money to keep changing that, they can swap it out for something else more foam or even filter floss like i do, i tested the filter and in fact it increased my lph not by much but it did increase i still change my floss as i can but i feel the floss is more beneficial to me than the carbon
 
same with my new filter's i have for my new tank it also have a very thin carbon pad phosphate pad and the thinnest filter floss pad known to man kind, IMO il be getting rid of all them and maybe just pitting filter floss in seeming this filter is way over sized for the tank i can afford to loose lph if so and alter the filters, again i personally re arrange the media inside, i have mechanical filtration obviously at the bottom but some filters not all then have bio then foam then bio then foam like my aqua manta i may change that to all foam then all bio, as i don't particular want the bio to get dirty with my tetra tec's that how i have it and the bio balls are clean all the time and you can see with the foam how clean the water gets as it passes up this in turn may change the way the filter works or acts but i have never had a bio issue with my tank, and the lph have stayed the same again i think its all down to what the user wants to do, there is not fixed right or wrong answer to anything as long as you don't kill fish then why not do it
 
and also, since writing my last post i have stoped using my 5400lph power head and i am just running my tank from the two filters to see how that will go with algae and stuff
 
makes me happy tho that eheim and aqua one state actually what there filter do, as to me the others are then lying to us

 

[Messi]

I hate Eheim filters and think they're hugely over-rated. I wouldn't like to rely on an Ehiem product.

 

[raptorrex]

yes, also if your filter dose not have the ability to reduce the flow eheim do inline taps or stoppers that will also reduce the flow this is what i plan to do with my filter as it is ridiculously over powered for my new tank but i rather have the flow restricted than not enough

 
and @ raptorrex
 
i diss agree with changing the media inside the filter can alter the way the filter works in a bad way and could be both good or bad, it all depends on the user, for example my old filters have carbon now from my research carbon is good but not needed and after a few weeks to a month dose not do its primary job and needs to be replaced for the users that don't have the ability or the money to keep changing that, they can swap it out for something else more foam or even filter floss like i do, i tested the filter and in fact it increased my lph not by much but it did increase i still change my floss as i can but i feel the floss is more beneficial to me than the carbon

 
firstly using tap to slow flow will not work. the only way to control flow is to adjust the speed of the power head. closing taps just increases the water speed. that is until the restriction causes the motor to pop.
I'm sorry but this is very basic stuff to be so wrong about. especially when it is dressed up as advice.
no real knowledge of hydrodynamics? then find out or keep shtum.
 
the placement and type of media used directly affects both flow and bio action.
flow is obvious, more dense media will restrict flow.
bio action is simple too. the water needs to spend enough time in contact with the bio media, but not too long. so the depth and shape of the media have a direct effect on bio action.
 
the simple change of media from Efi substrate  ( rough broken chunks of ceramic media) to Efi substrate pro (smooth round balls of media) drastically reduced "clumping" (areas where the media had bound in lumps) this not only allowed the filter to work longer between cleans, but also increased water penetration so more waste could be dealt with on each pass.
 
a stocked heavily planted tank will need (or should) less bio filtration but much more mechanical filtration. replacing a tray of bio for a tray of mech media would greatly help filtration in this case
 
media, and how its placed is vital to an effective filter.

 

[TwoTankAmin]

I am ignorant so I would appreciate it if raptor would explain to me what the difference is between using a valve on the output side of a pump or canister filters differs from the effects of head. This refers to how high the return must lift the water to get it to wherever it goes. Here is an example from the Danner site re their Supreme Model 5 Mag Drive pump.
 

• Nominal: 500 GPH
• Watts: 49
• GPH at 0': 570
• GPH at 1': 480
• GPH at 3': 425
• GPH at 5': 325
• GPH at 7': 205
• GPH at 10': -
• GPH at 15': -
• Shutoff: 10.5'

As you can see the flow rate drops as the number of feet (symbol ' ) increases. At 10.5 feet of head the flow stops.
 
What I was told many years ago by a gent who was a hands on installer of huge pumping systems was that one can always restrict the output flow but one should never ever restrict the intake side.

Duty Point
The point on the curve where the flow and head match the application's requirement is known as the duty point. A centrifugal pump always operates at the point on it's performance curve where its head matches the resistance in the pipeline. For example, if the pump shown above was fitted with a 6 inch impeller and encountered 100 feet of resistance in the pipeline, then it would operate at a flow of approximately 240 gallons per minute and 100 feet of head. It is important to understand that a centrifugal pump is not limited to a single flow at a given speed. Its flow depends on the amount of resistance it encounters in the pipeline. To control the flow of a centrifugal pump it is normally necessary to restrict the discharge pipeline, usually with a valve, and thus set the flow at the desired rate. Note: Generally speaking, do not restrict a pump's flow by putting a valve on the suction line. This can cause damage to the pump!

From http/www.pricepump.com/pumpschool/psles2.html
 
Now if you want a more scientifically oriented explanation, you could read here. What it will tell you is restricting output flow with a valve is just fine but never restrict the intake due to cavitation. (Please note this is true when pumping liquids but does not apply when pumping gases.)
 
Instrument Engineers' Handbook, Fourth Edition, Volume Two: Process Control
Edited by Bela G. Liptak
http/books.google.com/books?id=TxKynbyaIAMC&pg=PA2104&lpg=PA2104&dq=restricting+pump+flow&source=bl&ots=jwvjIRawzM&sig=9s7nTmnaUW84FNjIZjhzd9nsvbI&hl=en&sa=X&ei=Me17UabrHYWl4APStYG4CA&ved=0CDwQ6AEwAjgK#v=onepage&q=restricting%20pump%20flow&f=false
(Apparently it is possible to DL this as an Ebook for free if one so desires.)
 
Moreover, the use of controlling the flow via pump speed was developed for applications using large pumps where the waste of energy associated with restricting the output and/or using a flow around diverter were expensive control methods because of how much energy was wasted. This is not a consideration in the small scale pumps used in fish tanks.
 
Anyhow, maybe all the above is not correct and Raptor will straighten me out. I do not have much education in the area of hydrodynamics and have probably gotten it all wrong.

 

[Zikofski]

for a start, the reduced flow using taps works perfectly tried and tested, ALSO, the impellers are built well, very well, i ran mine to almost destruction and still could not destroy it, even ran it hot without water running through it for several hours and did not melt or break so i'm sure they can cope with a little increased pressure and stress.
 
and with the media i agree and that is why i change my media to suite the tank its in i have heavily planted tank so that why i have more mechanical media than bio and also have more polishing media for the crystal clear water never ever had a failure of filter they seem indestructible unless you take a sledge hammer to it
 
trust me i test things out i like to see what things can do so how they break if they break because if they do i want to know before it dose so i can get spares especially with the important stuff like heater's & filter's