Adding a Second Filter to Tank

[post2338]

I currently have a 46 gallon tank with an Eheim 2213 filter that is currently cycling. When the tank is fully cycled, I plan on stocking it over time to a medium to medium-high fish load. I am toying with adding another Eheim 2213 thinking that increased mechanical and biological filtering would be good for the fish along with increased aeration. I also like the benefit of a back-up should one need servicing and you could stagger the filter cleaning with minimal impact.

Is this over-kill or a smart thing to do? What are the drawbacks to this idea? Does anyone have alternative recommendations?

Thanks!

 

[JSchmidt]

Not overkill at all. It makes a lot of sense to distribute filtration across more than one filter. Redundancy protects against any single filter failing and wiping out your tank. It's hard to say if you need additional aeration; if your fish are OK and don't seem to be gasping, you probably have plenty of oxygen in the water. Still, running two (or more) filters is almost always a good idea. You might have to get creative to dissipate the current, although a pair of 2213s shouldn't produce that much.

Good luck,
Jim

 

[Philbe]

I think you'll find to a person that everyone would suggest 2 filters. And just for the reasons that you are thinking. In your case, with the load you are planning, the extra mech and bio filtration can only be a benefit.
I have on my 90 gal cichlid tank with a Filstar XP3 and an Emp 400. I went with the HOB as the second filter as I find it very easy to clean or replace the media, whereas the canister get it's cleaning every second or third time the Emp does.

Phil

 

[daveedka]

I run at least two filters on all tanks, even my 10g snail/ q tank is doubled up. Stabiility and easy maintenance are two of my favorite things.
Dave

 

[anonapersona]

Double but different

I like to use different types of filters as the second filter. This helps to make up for any bad points of the first filter. The 2213, for example is going to be nasty after a long power outage, and it will start right up when power returns. So, to compliment that, you'd want a filter that will be OK after a longish power outage and will also start right up. Something like a Penguin with biowheels might be a good choice, open to the air so not toxic with power outages, starts right up. Or an airpowered sponge with a battery operated airstone that starts up when the power goes out.

 

[geoffgarcia]

I know I'm in the minority here, but I think its overkill
just get a single bigger filter if you must
I highly doubt anyone can change my mind on this issue, but I'd love to hear more justification on why its better.

Redundancy protects against any single filter failing and wiping out your tank.

jim, how is a filter failing going to wipe out your tank? I turn my filters off from time to time for days or weeks just for the heck of it...how is it going to wipe out a tank (fresh water) if it fails?
(unless oxygen is an issue because of a lack of plants)

You might have to get creative to dissipate the current

just use a return bar with multiple outlets for the water to expel

easy maintenance are two of my favorite things.

Dave, how is having to maintain 2 filters easier than maintaining 1?

 

[daveedka]

Dave, how is having to maintain 2 filters easier than maintaining 1?

Maintaining two would be the same theoretically as maintaining one. tow of identicle size would plug up half as fast as one of the same size, or at precisely the same speed as 1 twice the size.
However in reality, stability is greatly increased due to redundancy, and also the points mentioned by anonapersona. Two different types of filters, compliment each other. In addition, I don't have nearly the concern of preserving bio- colonies that folks with one filter do. I can remove change, and wash media any way I chose, 1 filter at a time. I never have to worry about mini-spikes, rinsing things in tank water, or whether or not my bio-filtration has been hindered. If I don't have time this weekend to swap out sponges, I know my filters will go weeks without a problem. Secondly all of my tanks run an RFUG, that requires less maintenance IME than any other setup or filter in existance. When I do a water change I swap the intake sponges, and throw the dirty ones in the maytag. other than that they are maintenance free. Stability is a key in long term fishkeeping, and excessive bio and mechanical filtration create stability, which reduces stress and reduces the need for constant perfect maintenance.
I may chose to do maintenance every week, but with my systems I don't have to in order to keep things stable.
dave

 

[hey]

jim, how is a filter failing going to wipe out your tank? I turn my filters off from time to time for days or weeks just for the heck of it...how is it going to wipe out a tank (fresh water) if it fails?
(unless oxygen is an issue because of a lack of plants)

Depends on the kind of fish, and as you mentioned, # of plants if any. Neon tetras with no filter fall like flies

 

[geoffgarcia]

Maintaining two would be the same theoretically as maintaining one. tow of identicle size would plug up half as fast as one of the same size, or at precisely the same speed as 1 twice the size.

if you have one larger filter then you only need to clean one filter. If you have 2 smaller filters you need to clean 2.
So its not the same

I don't have nearly the concern of preserving bio- colonies that folks with one filter do. I can remove change, and wash media any way I chose, 1 filter at a time. I never have to worry about mini-spikes, rinsing things in tank water, or whether or not my bio-filtration has been hindered. If I don't have time this weekend to swap out sponges, I know my filters will go weeks without a problem. Secondly all of my tanks run an RFUG, that requires less maintenance IME than any other setup or filter in existance. When I do a water change I swap the intake sponges, and throw the dirty ones in the maytag. other than that they are maintenance free. Stability is a key in long term fishkeeping, and excessive bio and mechanical filtration create stability, which reduces stress and reduces the need for constant perfect maintenance.

I haven't done research on this, but I think bio colonies in filters (with the exception of wet dry & bio wheels) is highly over rated...I'd bet that in most tanks 80-90% of the "bio colonies" are IN the tank, and not in the filter...I see almost 0 difference in my fish behavior nor my water params when I turn on my filters or clean them. anything with surface area touching the water is gonna be covered in these colonies, its not limited to whats in your filter. Of course current going over them helps, but honestly, if water is surging past these sponges at lightning speed I can't imagine how effective these colonies can be...its like food flying by you on a fast conveyor belt...you dont have time to grab it...(granted this is also just a theory of mine and I admit I know next to zero about the biology of this stuff)

I think those that notice the larger impacts are peeps that use chemical filtration, and obviously thats the downfall on relying on something like that.

Finally, do filters really fail? I've had about 6 filters on 4 tanks in the past 7 years and have never had one fail....

 

[anonapersona]

Finally, do filters really fail? I've had about 6 filters on 4 tanks in the past 7 years and have never had one fail....

Wow, well, I've had a whisper fail to restart after a power outage. I've failed to open shutoff valves on one canister. I've had two impellor covers to break during cleaning canisters. I've had a part fall in between canister baskets that caused the head to not seal correctly and the baskets to warp. I've overfilled baskets and caused a leak at the head gasket. I've used incorrect lubricant on gaskets and found they were stiffening and starting to fail. I've boiled the parts of an airdriven sponge filter and warped the uplift tube. I've cleaned an impellor and put it on the floor where it picked up a stray staple and then put it and the staple back into the unit and damaged the impellor assembly. Most of these things caused either leaks or parts replacement, but if simply putting the unit into a bucket wasn't enough to make it usable, then I had to take the filter out of service until it was repaired. So, that tank had to rely on the backup filter or I've had to improvise one quickly.

And I've managed to do all this in just 2 years of keeping fish, running 7 or 8 tanks at a maximum.