What System Of Filtration Would Be Best?

[jazz298]

Alright, I have a 90 gallon tank yet to be set up (don't have a stand yet).
So I thought now would be a good time to find out about the filtration

It's going to have african cichlids, I dont know what kind yet.. but it WILL be over stocked by the slightest.

So my question is, can I get away with using a canister filer? Fluval to be exact, UNLESS of course another brand would be better, I'd just have to wait to go out of town. Fluval is all that is available where I live..

Or would a sump be better? And what size would it need to be?

Canister would be better for ME, but what would be better for my tank, and the fish???

 

[Ace Of Spades]

Alright, I have a 90 gallon tank yet to be set up (don't have a stand yet).
So I thought now would be a good time to find out about the filtration

It's going to have african cichlids, I dont know what kind yet.. but it WILL be over stocked by the slightest.

So my question is, can I get away with using a canister filer? Fluval to be exact, UNLESS of course another brand would be better, I'd just have to wait to go out of town. Fluval is all that is available where I live..

Or would a sump be better? And what size would it need to be?

Canister would be better for ME, but what would be better for my tank, and the fish???

you could use 2x Fluval FX5 If your planning to overstock

 

[jgray152]

I wouldn't go with 2 Fx5s. For 2 reasons.
1) If you were going to spend that much money I would get One Ehiem 2080 for less than two Fx5s.
Although 2 Fx5s will move 1100 GPH where One Ehiem would move about 450GPH. Two Ehiems would move about 800-900GPH at over twice the cost of two Fx5s. But, it would take 2 Fx5s to have te bio capacity of one Ehiem.
2) The Fx5 runs at about 50-60watts. Thats 100-120watts of continuous power if you were to use 2 Fx5s. The Ehiem I think is only around 30watts.


You could have one Fx5 and do fine with bio filtration. Only problem with the Fx5 is that I would reccomend to use all 3 of the center baskets for bio media which doesn't leave any place for fine filtration. This is why im looking into finner foam to replace the original ones. For you, you might be able to use 2 of the center baskets and have the top bakset for fine filtration but for an overstocked aquarium I would go with all 3 baskets.

 

[darrel69]

90gal = 340 litres i think....

So whatever you choose, your going to want two or more filters that together turn over at the very least 3400litres per hour, thats 10x turnover.

You could get away with 6x turnover if you start with juvies (which is 2040lph), but for adults 10x at least. Preferably 14/16x if you plan on really overstocking.

Africans can be really messey fish, the more fish you have, the dirtier your water will be.... the more times your water turns over, the cleaner it will be for them. Resulting in healthy happy fish

Good Luck.

 

[jumpman]

On my 90 gallon Tropheus tank I run an Eheim 2028 and an Eheim 2217 with a powerhead for extra circulation.

Two 2028s would be plenty of filtration even if overstocked slightly, IMO.

 

[CFC]

10x turn over is a bit over the top, unless you are keeping mountain stream dwelling fish which need fast flowing water then 5x per hour turn over through a decent selection of mechanical and biological filter media (not sponges) will give all the filtration you are ever going to need on a tropical tank. Filtration is more about surface area to volume ratio's of the biological media than how fast you can push the water through it, a filter with the right ammount of a hi tech filter medium like Eheim Efi Substrat Pro but only a 3x per hour turn over will still biologicaly out perform a filter packed with sponges cycling 10x per hour.


90 gallons isnt really that big so unless you are good with the DIY and like fiddling about with pipes and pumps then a sump is unessesary, one big canister filter or two smaller ones will be more than ample. My personal recomendation would be to use two Eheim Classic 2217s as they give good value for money and have a large ammount of media space, but they aren't everyones cup of tea as they are very basic and come with none of the fancy gadgets that more recently designed filters have, they have however stood the test of time and many long time experienced hobbiests have Eheim Classic filters that have been running for 20 years or more.

 

[Nim]

I had my 90 gallon (not african cichlid though) over stocked and a eheim 2215 + a cheap sacem 1500 with my own media and compartments working on the tank very well. I am an advocate of older style eheims as I think they are much more customizable then the new fluvals or tetra tec etc. where they have divided the canister into chambers.

Nim

 

[darrel69]

Two 2028s would be plenty of filtration even if overstocked slightly, IMO.

10x turn over is a bit over the top, unless you are keeping mountain stream dwelling fish which need fast flowing water then 5x per hour turn over through a decent selection of mechanical and biological filter media (not sponges) will give all the filtration you are ever going to need on a tropical tank. Filtration is more about surface area to volume ratio's of the biological media than how fast you can push the water through it, a filter with the right ammount of a hi tech filter medium like Eheim Efi Substrat Pro but only a 3x per hour turn over will still biologicaly out perform a filter packed with sponges cycling 10x per hour.

And i thought i was being a little on the low side!! ... 5x turnover is way to small imo. Ive always known 5&1/2x turnover to be the absolute bare minimum, and thats on a juvie only tank... 10x turnover minimum for a fully stocked tank with fully grown adults. Thats if you want healthy fish anyways....

Ferris even recommends more towards 20x turnover for a really overstocked adult tank.

And surely water would be alot cleaner if it was turned over 10x rather than 3x ?

 

[Nim]

I think some concepts are getting mixed here. 20x would be a bare minimum for a saltwater tank with live rock. Live rock needs this amount of flow around the tank for it to be able to act as a biological filter. Freshwater does not have such requirements and if there is good biological media in the canister then anything over 3x the volume of the tank should be enough (this is for medium sized tanks, for smaller tanks it may be 10x). Once the tank has matured and there is enough surface area for the bacteria coloney to survive, having 3 times or having 50 times will make no difference. 10x IMHO would be an overkill.

Considering that I would have needed 900GPH (3500lph) of flow? Unless I was keeping a 2ft wallago attu in the tank or a couple of 12" oscars, I dont see the reason. Also, I think malawi cichlids dont produce as much waste as predatory fish as their diet mainly consists of greens.

A 2000LPH canister or a 1000LPH + 1500LPH should be sufficient IMO.

Nim

Two 2028s would be plenty of filtration even if overstocked slightly, IMO.

And surely water would be alot cleaner if it was turned over 10x rather than 3x ?

It really would not be., Purpose of a filter is biological so unless you manage to increase the surface area by 10 times, it really would not make much difference.

Nim

 

[Ferris]

As much as i hate to disagree with CFC 10x is ideal for Mbuna tanks (not all African tanks). My 65 gal has a turnover just short of 15x without blowing the fish around at all. The flow is not as strong as you might expect and is all directed at the surface.

I completely agree with the comments re the type of media etc though and i also use and highly reccommend substrat pro.

 

[CFC]

Most marine tanks only have 20x turn over, to put that much current into a freshwater tank is just wasting power and completely unnecessary.

How do you think people with huge tanks manage to filter their tanks? Do you really think that I run a 18,000 gph pump to run the filtration on my 900g tank? Well i don't, i run a 2900gph pump through 50kg of filter media to filter the waste's from fish bigger than some peoples tanks.

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?

 

[Ferris]

I should add that most figures quoted by filter manufacturer's do not take into account filter media and the flow restriction that causes so a filter rated at 1200LPH in reality will probably do something nearer 800LPH.

The figure i quoted of nearly 15x tank turnover per hour is also based on filter manufacturer's stats (as i can't be bothered to work out the actual myself ) so my actual tank turnover will be nearer 10x.

The key difference with Mbuna tanks and the need for massive filtration is the heavy overstocking required to make such tanks work. The individual fish do not produce huge amounts of waste but collectively it can be like the equivalent of trying to cope with 4 adult Oscars in a standard 55 gallon tank. Because of this, in Mbuna tanks the mechanical filtration is just as important as biological.

 

[darrel69]

ok, there's comments coming from both sides that make sense... I think im going to have a look round a thew other forums to see what their opinions are, and what filteration they have on their African tanks.

 

[jgray152]

10x is a little much I think I know ferris has his opinion and CFC another. I feel as long as you have the volume in the filter and can get the water in the tank moving enough so that there is no stagnent water that it should be fine.

 

[CFC]

I should add that most figures quoted by filter manufacturer's do not take into account filter media and the flow restriction that causes so a filter rated at 1200LPH in reality will probably do something nearer 800LPH.

The figure i quoted of nearly 15x tank turnover per hour is also based on filter manufacturer's stats (as i can't be bothered to work out the actual myself ) so my actual tank turnover will be nearer 10x.

The key difference with Mbuna tanks and the need for massive filtration is the heavy overstocking required to make such tanks work. The individual fish do not produce huge amounts of waste but collectively it can be like the equivalent of trying to cope with 4 adult Oscars in a standard 55 gallon tank. Because of this, in Mbuna tanks the mechanical filtration is just as important as biological.

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

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.

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.