Overfiltration A Myth?

[statenfish]

I have a tendency to overfilter my tanks eg. three rena xp3 filters on one 90 gallon and a fluval 305 and one xp3 and one xp4 on my 90 gallon community tank. Most experts go nuts when they hear what im running. i havent lost a fish in over a year and you can drink the water. So why all the commotion regarding overfiltering?

 

[tenohfive]

I've never come across an issue with overfiltration - as long as you've got mature filter media running it shouldn't be an issue.

The problem might be flow rate - with 3 big filters it might be too much water flow. Some fish (such as Danio's, rainbows, WCCM's and some catfish) love fast moving water. For others though they may be less comfortable.

I don't claim to be an expert, but where I can I use twice as much filtration as is required minimum. Very good to have a backup.

 

[Rooster]

I would say it IS possible to overdo it.... at least from a biological point of view !
Your tank can only produce a finite amount of waste, which is food for the filter... so bacteria will thrive until the food is exhausted - thats nature in a nutshell !
So, you will only ever have the "right" amount of bacteria for your tank once its mature, adding more space for it to live in (on?) shouldnt make any difference IMO ... the newer stuff WILL become populated, but at the expense of the old stuff.

Thats my thinking.

 

[loraxchick]

the bacteria would colonize all filter media, no? just spread itself out over however many filters you have. might be less per filter but total colony volume would be essentially the same as if you only had one filter...one filter breaks down, for example and then the existing colonies now have more "food" and would grow accordingly on the still working filters. Once a colony is established, bacteria grow VERY fast when they have enough food. at least my experience in microbiology lab settings. i think more filters would be better.

 

[JimShorts]

My friend runs 100 gallons worth of filtration on his 55 gallon tank. As long as the amount of food for the bacteria stays the same, there should be no difference in the amount of nitrifying bacteria in a tank with one filter and the same tank with two filters. There will be the same amount of bacteria, they'll just be spread out over a larger area. Which if you ask me is good, because if one filter dies, you still have the other one running until you can get a replacement.

The only potential problem I can see is if you have too much current for the fish you are keeping. Obviously two 20-gallon filters running in a 5 gallon tank with a betta in it would qualify as overfiltration and would not be ideal for the betta.

 

[Schmill]

With one filter, it dies. All the bacteria are in that filter, if you don't sort it quickly the bacteria will die too.
=
You are in big trouble - Fish-In Cycle Time!

With two filters, one dies. Half (if the filters are matched), of the bacteria is in that filter, if you don't do something quickly the bacteria will die too.
=
You are not in SO much trouble, the other filter will try to compensate and is already 50% cycled for the fish load of the tank. You'll likely have a mini-cycle which you'll have to keep an eye on, but at least you'll have a good headstart on it

 

[raptorrex]

I have a tendency to overfilter my tanks eg. three rena xp3 filters on one 90 gallon and a fluval 305 and one xp3 and one xp4 on my 90 gallon community tank. Most experts go nuts when they hear what im running. i havent lost a fish in over a year and you can drink the water. So why all the commotion regarding overfiltering?

i would turn one filter over to mechanical filtration, with just course sponges and filter floss. if you clean it once a week, it should not build up any bio colony, leaving the other two to handle the bio action. just one point of caution. don't use carbon in any of your filters,. not only is there a, possibility, of leach back. but carbon does remove some vital elemrnts from the water, its probably the only case where over filtration is possible.

 

[statenfish]

I was toying with the idea of making one filter strictly mechanical. i have a rena xp3 and i was wondering hor i do this? what should i be running in each basket?

 

[raptorrex]

I was toying with the idea of making one filter strictly mechanical. i have a rena xp3 and i was wondering hor i do this? what should i be running in each basket?

just add course filter sponge and some floss. that should do the trick.

 

[pastabake]

Over filtration is an oxymoron.

You can only ever filter out what is there and going beyond that apart from being a talking point is plain silly.

As for the two is better than one ... well one working and one still in its box (free from mechanical wear etc) is even better.

So in a nut shell you've either got enough filtration to do the job or you haven't ... adding more filters is a bit like putting a fat exhaust on your car and expecting it to go faster ...

However, there is a belief among some scientists that when food becomes scarce the bacteria doesn't just die off but will enter a dormant stage ... so theoretically having excess filtration may work by proving a pool of dormant bacteria ready to deal with Nitrite or Ammonia spikes. A caveat though is that the bacteria is part of a colony and there are 'predator' species that would happily make a meal of such dormant bacteria ...